Optics Letters via MedWorm.com MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Optics Letters' source. Mon, 06 Feb 2012 20:25:00 +0100 Vacuum ultraviolet frequency combs generated by a femtosecond enhancement cavity in the visible http://www.medworm.com/index.php?rid=5656919&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-503 We present the first (to our best knowledge) femtosecond enhancement cavity in the visible wavelength range for ultraviolet frequency comb generation. The cavity is seeded at 518 nm by a frequency-doubled Yb fiber laser and operates at a peak intensity of 1.2×10^13??W/cm^2. High harmonics of ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656919 Sat, 04 Feb 2012 01:20:20 +0100 5656919 Experimental evidence of extreme value statistics in Raman fiber lasers http://www.medworm.com/index.php?rid=5656918&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-500 We present an experiment in which the intracavity broadened spectrum of a Raman fiber laser is sliced by using a narrow-bandwidth optical filter. High-contrast fast fluctuations of the Stokes power are observed at the output of the optical filter. The statistics of the power fluctuations strongly ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656918 Sat, 04 Feb 2012 01:20:20 +0100 5656918 Active coherent beam combination of two high-power single-frequency nanosecond fiber amplifiers http://www.medworm.com/index.php?rid=5656917&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-497 We report on active coherent beam combining of two single-frequency nanosecond fiber amplifiers by using stochastic parallel gradient descent algorithm. Each fiber amplifier produces an average power of more than 100?W by using three-stage cascaded amplification. The two laser beams are actively ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656917 Sat, 04 Feb 2012 01:20:20 +0100 5656917 Radio frequency interrogated actively mode-locked fiber ring laser for sensing application http://www.medworm.com/index.php?rid=5656916&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-494 This paper proposes an actively mode-locked fiber ring laser for sensing applications. Mode-locking of the laser is achieved by driving an electro-optic amplitude modulator at an RF corresponding to the fundamental beat frequency between the longitudinal modes. The change of the cavity length ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656916 Sat, 04 Feb 2012 01:20:20 +0100 5656916 Ultrafast laser inscription of Bragg-grating waveguides using the multiscan technique http://www.medworm.com/index.php?rid=5656915&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-491 We report the fabrication of high-strength (>30??dB) first order Bragg-grating waveguides in borosilicate glass substrates using ultrafast laser inscription. The cross section of each waveguide was controlled using the well known multiscan fabrication technique, where the desired waveguide cross ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656915 Sat, 04 Feb 2012 01:20:20 +0100 5656915 Photonic crystal nanocavity laser in an optically very thick slab http://www.medworm.com/index.php?rid=5656914&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-488 A photonic crystal (PhC) nanocavity formed in an optically very thick slab can support reasonably high-Q modes for lasing. Experimentally, we demonstrate room-temperature pulsed lasing operation from the PhC dipole mode emitting at 1324 nm, which is fabricated in an InGaAsP slab with thickness (T) ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656914 Sat, 04 Feb 2012 01:20:19 +0100 5656914 Anderson localization in a periodic photonic lattice with a disordered boundary http://www.medworm.com/index.php?rid=5656913&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-485 We investigate experimentally the light evolution inside a two-dimensional finite periodic array of weakly coupled optical waveguides with a disordered boundary. For a completely localized initial condition away from the surface, we find that the disordered boundary induces an asymptotic ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656913 Sat, 04 Feb 2012 01:20:19 +0100 5656913 The role of self-trapped excitons and defects in the formation of nanogratings in fused silica http://www.medworm.com/index.php?rid=5656912&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-482 We investigate the role of self-trapped excitons (STEs) and defects in the formation of femtosecond laser pulse induced nanogratings (NGs) in fused silica. Our experiments reveal strongly enhanced NG formation for pulse separations up to the STE lifetime. In addition, the absorption spectra show ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656912 Sat, 04 Feb 2012 01:20:19 +0100 5656912 Characterization of a photonic strain sensor in silicon-on-insulator technology http://www.medworm.com/index.php?rid=5656911&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-479 Recently there has been growing interest in sensing by means of optical microring resonators in photonic integrated circuits that are fabricated in silicon-on-insulator (SOI) technology. Taillaert et al. [Proc. SPIE6619, 661914 (2007)PSISDG0277-786X10.1117/12.738412] proposed the use of a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656911 Sat, 04 Feb 2012 01:20:19 +0100 5656911 Cascaded frequency upconversion for high-speed single-photon detection at 1550 nm http://www.medworm.com/index.php?rid=5656910&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-476 We present a device for two-stage frequency upconversion of single-photon-level signals in the 1.55 μm telecom band to the green spectral region with low excess noise, suitable for detection by low-timing-jitter silicon single-photon avalanche photodiodes (APDs). We achieve a net conversion ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656910 Sat, 04 Feb 2012 01:20:19 +0100 5656910 Image formation in CARS and SRS: effect of an inhomogeneous nonresonant background medium http://www.medworm.com/index.php?rid=5656909&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-473 We investigate the role of a spatially inhomogenous nonresonant background medium on several Raman-based imaging modalities. In particular, we consider a small resonant bead submerged in a spatially heterogeneous nonresonant χ^(3) background. Using detailed 3D electrodynamic simulations, we ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656909 Sat, 04 Feb 2012 01:20:19 +0100 5656909 Adaptive slit beam shaping for direct laser written waveguides http://www.medworm.com/index.php?rid=5656908&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-470 We demonstrate an improved method for fabricating optical waveguides in bulk materials by means of femtosecond laser writing. We use an LC spatial light modulator (SLM) to shape the beam focus by generating adaptive slit illumination in the pupil of the objective lens. A diffraction grating is ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656908 Sat, 04 Feb 2012 01:20:19 +0100 5656908 Polarization phase-shifting Newton interferometer for plane optical surface measurements http://www.medworm.com/index.php?rid=5656907&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-467 This Letter introduces a polarization phase-shifting Newton interferometer that can be utilized for plane optical surface measurements, a setup constructed to realize the interferometer, and the experimental results from the use of the setup. The results confirm not only the validity but also the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656907 Sat, 04 Feb 2012 01:20:19 +0100 5656907 Low-threshold single-wavelength all-fiber laser generating cylindrical vector beams using a few-mode fiber Bragg grating http://www.medworm.com/index.php?rid=5656906&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-464 We propose and demonstrate a low-threshold single-wavelength all-fiber laser generating cylindrical vector beams using a few-mode fiber Bragg grating. Both radially and azimuthally polarized beams have been generated with very good modal symmetry and polarization purity higher than 94%. The ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656906 Sat, 04 Feb 2012 01:20:19 +0100 5656906 Spontaneous subpicosecond pulse formation with pulse repetition rate of 80 GHz in a diode-pumped Nd:SrGdGa_3O_7 disordered crystal laser http://www.medworm.com/index.php?rid=5656905&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-461 We explore the operation of spontaneous mode locking in a diode-pumped Nd:SrGdGa_3O_7 disordered crystal laser. The first- and second-order autocorrelations are simultaneously performed to evaluate the temporal characteristics. An 80 GHz pulse train with a pulse duration as short as 616 fs is ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656905 Sat, 04 Feb 2012 01:20:19 +0100 5656905 Ultrahigh-resolution full-field optical coherence tomography using spatial coherence gating and quasi-monochromatic illumination http://www.medworm.com/index.php?rid=5656924&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-458 We developed an ultrahigh-resolution full-field optical coherence tomography (FF-OCT) microscope that is based on the spatial, rather than the temporal, coherence gating. The microscope is capable of observing three-dimensional microbiological structures as small as ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656924 Fri, 03 Feb 2012 05:00:00 +0100 5656924 Group delay locking of coherently combined broadband lasers http://www.medworm.com/index.php?rid=5656923&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-455 We demonstrate a method for single-detector coherent sensing and automated coalignment of group delays in a coherently combined laser array, enabling robust coherent combining of broadband sources despite initial path mismatches exceeding the laser coherence length. The method is based on ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656923 Fri, 03 Feb 2012 05:00:00 +0100 5656923 Nineteen-port photonic lantern with multimode delivery fiber http://www.medworm.com/index.php?rid=5656922&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-452 We demonstrate efficient multimode (MM) to single-mode (SM) conversion in a 19-port photonic lantern with a 50 μm core MM delivery fiber. The photonic lantern can be used within the field of astrophotonics for coupling MM starlight to an ensemble of SM fibers in order to perform ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656922 Fri, 03 Feb 2012 05:00:00 +0100 5656922 Determination of layer thickness and optical constants of thin films by using a modified pattern search method http://www.medworm.com/index.php?rid=5656921&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-449 We propose the use of a pattern search optimization technique in combination with a seed preprocessing procedure to determine the optical constants and thickness of thin films using only the transmittance spectra. The approach is quite flexible, straightforward to implement, and efficient in ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656921 Fri, 03 Feb 2012 05:00:00 +0100 5656921 Combined frequency conversion and pulse compression in nonlinear tapered waveguides http://www.medworm.com/index.php?rid=5656920&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-4-446 We suggest an application of pump-degenerate four-wave mixing process in tapered waveguides for generation of ultrashort pulses with central frequency tunable over the material transparency range. Our method can produce strongly compressed frequency-converted pulses in presence of group-velocity ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5656920 Fri, 03 Feb 2012 05:00:00 +0100 5656920 Fast maximum likelihood algorithm for localization of fluorescent molecules http://www.medworm.com/index.php?rid=5644080&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-413 A common task in microscopy is to fit an image of a fluorescent probe to a point spread function (PSF) in order to estimate the position of the probe. The PSF is often approximated as a Gaussian for mathematical simplicity. We show that the separable property of the Gaussian PSF enables a reduction ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644080 Tue, 31 Jan 2012 19:48:18 +0100 5644080 Bio-organism detection in one-dimensional photonic crystals using electromagnetically induced transparency http://www.medworm.com/index.php?rid=5644079&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-410 We propose an optical sensor that allows site-selective detection of a refractive index change occurring due to any infiltration such as a bio-organism in a porous one-dimensional photonic crystal (PC). We use the electromagnetically induced transparency (EIT) to detect and locate the infiltration. ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644079 Tue, 31 Jan 2012 19:48:18 +0100 5644079 Lighting spectrum to maximize colorfulness http://www.medworm.com/index.php?rid=5644078&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-407 The spectrum of modern illumination can be computationally tailored considering the visual effects of lighting. We investigated the spectral profiles of the white illumination maximizing the theoretical limits of the perceivable object colors. A large number of metamers with various degrees of ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644078 Tue, 31 Jan 2012 19:48:18 +0100 5644078 Toward an electrically pumped spaser http://www.medworm.com/index.php?rid=5644077&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-404 The use of surface plasmon polariton (SPP)-based waveguides can significantly reduce the size of optical interconnects, but the propagation length of SPPs is limited by Joule heating losses and does not exceed a few micrometers. In this paper, we present an SPP amplification scheme that utilizes ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644077 Tue, 31 Jan 2012 19:48:18 +0100 5644077 Double-pass self-spectral-calibration of a polarization state analyzer http://www.medworm.com/index.php?rid=5644086&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-401 We present a new method that allows efficient spectral calibration for a polarization state analyzer. The procedure does not require any additional polarization optical element other than the polarization state analyzer itself. It uses a double-pass technique that can be achieved up to a very good ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644086 Mon, 30 Jan 2012 05:00:00 +0100 5644086 Magneto-optical fiber sensor based on magnetic fluid http://www.medworm.com/index.php?rid=5644085&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-398 A novel magnetic field fiber sensor based on magnetic fluid is proposed. The sensor is configured as a Sagnac interferometer structure with a magnetic fluid film and a section of polarization maintaining fiber inserted into the fiber loop to produce a sinusoidal interference spectrum for ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644085 Mon, 30 Jan 2012 05:00:00 +0100 5644085 Graphene on SiC as a Q-switcher for a 2 μm laser http://www.medworm.com/index.php?rid=5644084&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-395 Double-layer graphene epitaxially grown on silicon carbide was used to Q-switch a Tm:YAG laser. Stable Q-switched laser pulses at the central wavelength of 2.01 μm were obtained. The maximum average output power, pulse repetition rate, and single pulse energy were 38 mW, 27.9 kHz, and 1.74 ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644084 Mon, 30 Jan 2012 05:00:00 +0100 5644084 Three-dimensional mid-infrared photonic circuits in chalcogenide glass http://www.medworm.com/index.php?rid=5644083&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-392 We report the fabrication of single-mode buried channel waveguides for the whole mid-IR transparency range of chalcogenide sulphide glasses (λ≤11??μm), by means of direct laser writing. We have explored the potential of this technology by fabricating a prototype three-dimensional ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644083 Mon, 30 Jan 2012 05:00:00 +0100 5644083 Stationary one-dimensional dispersive shock waves http://www.medworm.com/index.php?rid=5644082&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-389 We address shock waves generated upon the interaction of tilted plane waves with negative refractive index defects in defocusing media with linear gain and two-photon absorption. We found that, in contrast to conservative media where one-dimensional dispersive shock waves usually exist only as ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644082 Mon, 30 Jan 2012 05:00:00 +0100 5644082 Computational polarization imaging from a single speckle image http://www.medworm.com/index.php?rid=5644081&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-386 We experimentally demonstrate that imaging of the degree of polarization (DOP) can be achieved from a single intensity image acquired under coherent illumination. This computational technique is based on the analysis of the speckle characteristics in a statistically homogeneous neighborhood of the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5644081 Mon, 30 Jan 2012 05:00:00 +0100 5644081 Non-steady-state photoelectromotive force effect under linear and periodical phase modulation: application to detection of Doppler frequency shift http://www.medworm.com/index.php?rid=5635740&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-383 Non-steady-state photoelectromotive force effect in the presence of periodical and linear phase shift was investigated both theoretically and experimentally. It was shown that superposition of oscillating and linear movements of the interference pattern leads to the appearance of the sharp peak in ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5635740 Sat, 28 Jan 2012 01:35:16 +0100 5635740 Numerical and experimental investigation of long-period gratings in photonic crystal fiber for refractive index sensing of gas media http://www.medworm.com/index.php?rid=5635739&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-380 We have used the finite-difference frequency-domain (FDFD) method to simulate the core mode to cladding mode couplings in long-period gratings (LPGs) in photonic crystal fiber (PCF). Four sets of LPG-PCF have been fabricated with respective periodicities of 590, 540, 515, and 490??μm, ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5635739 Sat, 28 Jan 2012 01:35:16 +0100 5635739 26 nJ picosecond solitons from thulium-doped single-mode master oscillator power fiber amplifier http://www.medworm.com/index.php?rid=5635738&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-377 We report on an all single-mode master oscillator power fiber amplifier delivering high energy picosecond solitons at 1960 nm. The Bragg stabilized and self-starting oscillator delivers 62 pJ transform-limited pulses at 11.2 MHz pulse repetition frequency. Solitons are amplified in a core-pumped ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5635738 Sat, 28 Jan 2012 01:35:16 +0100 5635738 Single-mode whispering gallery lasing from metal-clad GaN nanopillars http://www.medworm.com/index.php?rid=5617310&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-374 An ordered hexagonal closed-packed nanopillar array is fabricated on GaN. A metal coating is then applied to encapsulate the pillars for promoting optical confinement within the cylindrical cavity. Room-temperature lasing at 373 nm is observed under pulsed excitation, at a lasing threshold of ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617310 Sun, 22 Jan 2012 01:20:24 +0100 5617310 Wideband perfect light absorber at midwave infrared using multiplexed metal structures http://www.medworm.com/index.php?rid=5617309&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-371 We experimentally demonstrate a wideband near-perfect light absorber in the midwave IR region using a multiplexed plasmonic metal structure. The wideband near-perfect light absorber is made of two different size gold metal squares multiplexed on a thin dielectric spacing layer on top of a thick ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617309 Sun, 22 Jan 2012 01:20:24 +0100 5617309 Enhanced downconversion of UV light by resonant scattering of aluminum nanoparticles http://www.medworm.com/index.php?rid=5617308&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-368 Metallic nanoparticles are known to enhance nonlinear optical processes due to a local enhancement of the optical field. This strategy has been proposed to enhance downconversion in thin film solar cells, but has various disadvantages, among which is the fact that the enhancement occurs only in a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617308 Sun, 22 Jan 2012 01:20:24 +0100 5617308 Ultracompact polarization converter with a dual subwavelength trench built in a silicon-on-insulator waveguide http://www.medworm.com/index.php?rid=5617320&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-365 The design and fabrication of an ultracompact silicon-on-insulator polarization converter is reported. The polarization conversion with an extinction ratio of 16 dB is achieved for a conversion length of only 10 μm. Polarization rotation is achieved by inducing a vertical asymmetry by forming ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617320 Fri, 20 Jan 2012 05:00:00 +0100 5617320 Integrated multimodal endomicroscopy platform for simultaneous en face optical coherence and two-photon fluorescence imaging http://www.medworm.com/index.php?rid=5617319&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-362 We report an all-fiber-optic scanning, multimodal endomicroscope capable of simultaneous optical coherence tomography (OCT) and two-photon fluorescence (TPF) imaging. Both imaging modalities share the same miniature fiber-optic scanning endomicroscope, which consists of a double-clad fiber with a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617319 Fri, 20 Jan 2012 05:00:00 +0100 5617319 Enhance the resolution of photonic crystal negative refraction imaging by metal grating http://www.medworm.com/index.php?rid=5617318&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-359 The resolution of imaging is limited by the missing of high-frequencies information. The superlens employing negative refraction can compensate for these components. But for the directional coupling of Bloch waves and the low coupling efficiency of large-angle waves, the resolution of subwavelength ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617318 Fri, 20 Jan 2012 05:00:00 +0100 5617318 Efficient thin-disk Tm-laser operation based on Tm:KLu(WO_4)_2/KLu(WO_4)_2 epitaxies http://www.medworm.com/index.php?rid=5617317&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-356 A diode-pumped thin-disk laser based on Tm:KLu(WO_4)_2/KLu(WO_4)_2 epitaxies is realized. The emission is in the 1850–1945 nm spectral range for Tm-doping between 5 and 15 at. %. The maximum slope efficiency of 47% with respect to the absorbed power obtained with 5 at. % ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617317 Fri, 20 Jan 2012 05:00:00 +0100 5617317 All-fiber polarization interference filters based on 45°-tilted fiber gratings http://www.medworm.com/index.php?rid=5617316&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-353 We report all-fiber polarization interference filters, known as Lyot and Lyot-Őhman filters, based on alternative concatenation of UV-inscribed fiber gratings with structure tilted at 45° and polarization maintaining (PM) fiber cavities. Such filters generate comb-like transmission of ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617316 Fri, 20 Jan 2012 05:00:00 +0100 5617316 Single-shot profilometry of rough surfaces using hyperspectral interferometry http://www.medworm.com/index.php?rid=5617315&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-350 The combination of white light interferometry with hyperspectral imaging (“hyperspectral interferometry”) is a recently proposed technique for single-shot measurement of 3D surface profiles. We consider for the first time its application to speckled wavefronts from optically rough ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617315 Fri, 20 Jan 2012 05:00:00 +0100 5617315 Time-domain multimode dispersion measurement in a higher-order-mode fiber http://www.medworm.com/index.php?rid=5617314&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-347 We present a new multimode dispersion measurement technique based on the time-of-flight method. The modal delay and group velocity dispersion of all excited modes in a few-mode fiber can be measured simultaneously by a tunable pulsed laser and a high speed sampling oscilloscope. A newly designed ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617314 Fri, 20 Jan 2012 05:00:00 +0100 5617314 High power (130 mW) 40 GHz 1.55 μm mode-locked distributed Bragg reflector lasers with integrated optical amplifiers http://www.medworm.com/index.php?rid=5617313&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-344 High output power 40 GHz 1.55 μm passively mode-locked surface-etched distributed Bragg reflector (DBR) lasers with monolithically integrated semiconductor optical amplifiers are reported. These are based on an optimized AlGaInAs/InP epitaxial structure with a three quantum well active layer ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617313 Fri, 20 Jan 2012 05:00:00 +0100 5617313 Full-field technique for measuring the spectral evolution of reconfigurable photonic filters http://www.medworm.com/index.php?rid=5617312&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-341 This Letter demonstrates a measurement technique based on frequency-to-time mapping and coherent detection, which enables the complete (i.e., amplitude and phase) characterization of dynamically reconfigurable photonic filters. We apply this technique to a unit cell from a silicon CMOS-compatible ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617312 Fri, 20 Jan 2012 05:00:00 +0100 5617312 Diode-pumped green Nd:YAG laser with Q-switch and mode locking http://www.medworm.com/index.php?rid=5617311&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-338 We propose a new method for achieving simultaneous operation of laser mode locking and the Q-switch technique using only a single acousto-optic modulator (AOM) with a traveling wave; this AOM was placed inside the cavity of a green-emission Nd:YAG laser. The further shortening of the lasing pulse ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5617311 Fri, 20 Jan 2012 05:00:00 +0100 5617311 Compact optical microfiber phase modulator http://www.medworm.com/index.php?rid=5604328&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-320 A compact optical microfiber phase modulator with MHz bandwidth is presented. A micrometer-diameter microfiber is wound on a millimeter-diameter piezoelectric ceramic rod with two electrodes. When a voltage is applied to the piezoelectric ceramic, the rod is strained, leading to a phase change ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604328 Thu, 19 Jan 2012 02:02:34 +0100 5604328 Solar blind photoconductivity in three-terminal devices of LaAlO_3/SrTiO_3 heterostructures http://www.medworm.com/index.php?rid=5604327&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-317 We report observations of photoconductivity in ultrathin films of LaAlO_3 grown on (001) SrTiO_3 at several deposition temperatures. The films show pronounced metallic behavior in the dark. The conductance of this metallic state can be enhanced by ultraviolet light (350–400 nm) of a few ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604327 Thu, 19 Jan 2012 02:02:34 +0100 5604327 Coherence–polarization mixing in resonance gratings http://www.medworm.com/index.php?rid=5604326&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-314 We show, using rigorous diffraction theory, that resonance gratings can be used to transfer partial spatial correlation to partial polarization even if the incident light beam is fully polarized. The phenomenon is based on the fact that either of the two orthogonal polarization components can be ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604326 Thu, 19 Jan 2012 02:02:34 +0100 5604326 Pure two-dimensional polarization patterns for holographic recording http://www.medworm.com/index.php?rid=5604325&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-311 Two-dimensional (2D) polarization patterns are achieved by the interference of two pairs of beams with perpendicular planes of incidence and orthogonal polarizations (i.e. linear or circular). In both cases, imposing a phase shift of π/2 between consecutive beams contains the amplitude ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604325 Thu, 19 Jan 2012 02:02:34 +0100 5604325 Design of metamaterial surfaces with broadband absorbance http://www.medworm.com/index.php?rid=5604324&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-308 A simple design paradigm for making broadband ultrathin plasmonic absorbers is introduced. The absorber’s unit cell is composed of subunits of various sizes, resulting in nearly 100% absorbance at multiple adjacent frequencies and high absorbance over a broad frequency range. A simple ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604324 Thu, 19 Jan 2012 02:02:34 +0100 5604324 Longitudinal-differential interferometry: direct imaging of axial superluminal phase propagation http://www.medworm.com/index.php?rid=5604323&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-305 We introduce and demonstrate a new interferometric method called longitudinal-differential (LD) interferometry, which measures the spatially resolved phase difference of the scattered field by an object relative to the illumination. This method is combined with a high-resolution interference ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604323 Thu, 19 Jan 2012 02:02:34 +0100 5604323 Widely tunable and ultrasensitive leaky-guided multimode fiber interferometer based on refractive-index-matched coupling http://www.medworm.com/index.php?rid=5604322&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-302 This investigation presents a simple, widely tunable, and ultrasensitive sensor that is based on a leaky-guided multimode fiber interferometer (MMFI) operated under refractive-index-matched coupling. By use of a material with an appropriate dispersion profile around the MMFI as a cladding yields ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604322 Thu, 19 Jan 2012 02:02:34 +0100 5604322 Ultrahigh infrared normal spectral emissivity of microstructured silicon coating Au film http://www.medworm.com/index.php?rid=5604321&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-299 We studied infrared normal spectral emissivity on quasi-periodic microstructured silicon, which was prepared by femtosecond laser irradiation in SF_6 ambient gas, coated with 100 nm thick Au thin film. The observed emissivity is higher than any reported previously for a flat material with a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604321 Thu, 19 Jan 2012 02:02:34 +0100 5604321 Terahertz bandpass filters using double-stacked metamaterial layers http://www.medworm.com/index.php?rid=5604320&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-296 Bandpass filters are reported based on double-stacked metamaterial layers separated by an air gap for operation at terahertz frequencies. Several stacking configurations were investigated designed for a ∼0.5??THz center frequency. The filters exhibited improved spectral transmission ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604320 Thu, 19 Jan 2012 02:02:34 +0100 5604320 Photoelastic response of alkaline earth aluminosilicate glasses http://www.medworm.com/index.php?rid=5604319&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-293 Understanding the structural origins of the photoelastic response in oxide glasses is important for discovering new families of zero-stress optic glasses and for developing a predictive physical model. In this Letter, we have investigated the composition dependence of the stress optic coefficient C ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604319 Thu, 19 Jan 2012 02:02:34 +0100 5604319 Aerosol lenses propagation model: erratum http://www.medworm.com/index.php?rid=5604318&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-292 In a previous paper [Opt. Lett.36, 3419 (2011)], credit was not given to a previous publication. The reference is given here. (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604318 Thu, 19 Jan 2012 02:02:34 +0100 5604318 Phase-matched third-harmonic generation in highly germanium-doped fiber http://www.medworm.com/index.php?rid=5604317&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-289 Phase-matched third-harmonic generation is demonstrated in a germanium-doped optical fiber. Green light at 514.4 nm is generated in an LP_03 mode when a pump field at ∼1543.3??nm is launched into the fiber in the fundamental LP_01 mode. The phase matching is achieved for a particular ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604317 Thu, 19 Jan 2012 02:02:34 +0100 5604317 Light localization in nonuniformly randomized lattices http://www.medworm.com/index.php?rid=5604316&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-286 We address Anderson localization of light in disordered optical lattices where the disorder strength varies across the transverse direction. Such variation changes the preferred domains where formation of localized eigenmodes is most probable, hence drastically impacting light localization ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604316 Thu, 19 Jan 2012 02:02:34 +0100 5604316 Polarization rotator for InP rib waveguide http://www.medworm.com/index.php?rid=5604315&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-335 A polarization rotator, suitable for integration in a polarization diversity optical receiver fabricated in InP technology, is proposed. The device, based on a two steps waveguide rotator, includes tapered input and output ports that provide very low insertion loss ( (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604315 Thu, 19 Jan 2012 02:02:34 +0100 5604315 Anderson localization in nonlocal nonlinear media http://www.medworm.com/index.php?rid=5604314&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-332 We theoretically and numerically investigate the effect of focusing and defocusing nonlinearities on Anderson localization in highly nonlocal media. A perturbative approach is developed to solve the nonlocal nonlinear Schrödinger equation in the presence of a random potential, showing that ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604314 Thu, 19 Jan 2012 02:02:34 +0100 5604314 A slow-light laser radar system with two-dimensional scanning http://www.medworm.com/index.php?rid=5604313&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-329 We propose a multi-aperture slow-light laser radar with two-dimensional scanning. We demonstrate experimentally that we can use two independent slow-light mechanisms, namely dispersive delay and stimulated Brillouin scattering, to dynamically compensate the group delay mismatch among different ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604313 Thu, 19 Jan 2012 02:02:34 +0100 5604313 Split-step finite-difference time-domain method with perfectly matched layers for efficient analysis of two-dimensional photonic crystals with anisotropic media http://www.medworm.com/index.php?rid=5604312&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-326 This Letter presents a split-step (SS) finite-difference time-domain (FDTD) method for the efficient analysis of two-dimensional (2-D) photonic crystals (PhCs) with anisotropic media. The proposed SS FDTD method is formulated with perfectly matched layer boundary conditions and caters for ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604312 Thu, 19 Jan 2012 02:02:34 +0100 5604312 Reflective fiber-optic refractometer based on a thin-core fiber tailored Bragg grating reflection http://www.medworm.com/index.php?rid=5604311&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-3-323 A novel reflective refractometer based on a thin-core fiber (TCF) sandwiched between a leading single-mode fiber (SMF) and a fiber Bragg grating (FBG) imprinted SMF stub was demonstrated. The reflection from the fiber stub occurs in two well-defined wavelength bands, corresponding to the Bragg core ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5604311 Thu, 19 Jan 2012 02:02:34 +0100 5604311 Laser profile reshaping in a Fabry–Perot thin film http://www.medworm.com/index.php?rid=5593606&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-283 We report the observation of non-Gaussian reflected and transmitted laser spatial profiles resulting from the excitation of resonant modes below the critical angle for total reflection in a Fabry–Perot cavity formed by a thin ∼7??um air film between two glass prisms. The observations ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593606 Fri, 13 Jan 2012 05:00:00 +0100 5593606 Enhanced photonic crystal cavity-waveguide coupling using local slow-light engineering http://www.medworm.com/index.php?rid=5593605&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-280 This Letter introduces an enhanced cavity-waveguide coupling architecture based upon slow-light engineering in a two-port photonic crystal system. After analyzing the system transmittance using coupled-mode theory, the system is probed experimentally and shown to have increased transmittance due to ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593605 Fri, 13 Jan 2012 05:00:00 +0100 5593605 Ronchi-grating-based measurement of photorefractive recording response time http://www.medworm.com/index.php?rid=5593604&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-277 We report on a simple technique for the measurement of the recording response time in photorefractive materials. Three different material samples were successfully measured, and their response times, as well as their dependence upon the recording/measurement light irradiance, were also determined ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593604 Fri, 13 Jan 2012 05:00:00 +0100 5593604 Optimized free-form optical trapping systems http://www.medworm.com/index.php?rid=5593603&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-274 We report a comprehensive process for designing and prototyping new and optimized optical trapping systems. A combination of traditional lens design strategies, simulation of optical forces, and high-end ultraprecision machining of optical free-form surfaces is applied to the realization of a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593603 Fri, 13 Jan 2012 05:00:00 +0100 5593603 Wideband plasmonic beam steering in metal gratings http://www.medworm.com/index.php?rid=5593602&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-271 We demonstrate controllable light deflection in thick metal gratings with periodic subwavelength slits filled with an active material. Under specific illumination conditions, the grating becomes nearly transparent and acts as a uniform optical phased-array antenna where the phase of the radiating ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593602 Fri, 13 Jan 2012 05:00:00 +0100 5593602 Intense 2.7 µm emission and structural origin in Er^3+-doped bismuthate (Bi_2O_3-GeO_2-Ga_2O_3-Na_2O) glass http://www.medworm.com/index.php?rid=5593601&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-268 The 2.7 μm emission properties in Er^3+-doped bismuthate (Bi_2O_3-GeO_2-Ga_2O_3-Na_2O) glass were investigated in the present Letter. An intense 2.7 μm emission in Er^3+-doped bismuthate glass was observed. It is found that ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593601 Fri, 13 Jan 2012 05:00:00 +0100 5593601 Scattering of electromagnetic waves by charged spheres: near-field external intensity distribution http://www.medworm.com/index.php?rid=5593600&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-265 This Letter treats the scattering of electromagnetic waves by an electrically charged spherical particle in near-field approximation. Particular attention is paid to the external intensity distribution at the outer edges of the particle. The difference between scattering by a charged sphere and an ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593600 Fri, 13 Jan 2012 05:00:00 +0100 5593600 Iterative retrieval of one-dimensional x ray wave field using a single intensity measurement http://www.medworm.com/index.php?rid=5593599&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-262 The problem of retrieving a complex function from the modulus of its Fourier transform has non-unique solutions in one dimension. Therefore iterative phase retrieval methods cannot in general be confidently applied to one-dimensional problems, due ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593599 Fri, 13 Jan 2012 05:00:00 +0100 5593599 Triggering and guiding high-voltage discharge in air by single and multiple femtosecond filaments http://www.medworm.com/index.php?rid=5593598&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-259 The abilities to trigger and guide high-voltage discharge by using single and multiple filaments (MFs) are experimentally studied. It is shown that the discharge voltage threshold can be reduced significantly in both regimes of single and MF; ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593598 Fri, 13 Jan 2012 05:00:00 +0100 5593598 Laser-written nanoporous silicon ridge waveguide for highly sensitive optical sensors http://www.medworm.com/index.php?rid=5593597&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-256 We report that low-loss ridge waveguides are directly written on nanoporous silicon layers by using an argon-ion laser at 514 nm up to 100 mW. Optical characterization of the waveguides indicates light propagation loss lower than 0.5??dB/cm at 1550 nm after oxidation. A Mach–Zehnder ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593597 Fri, 13 Jan 2012 05:00:00 +0100 5593597 Generation of megawatt peak power picosecond pulses from a divided-pulse fiber amplifier http://www.medworm.com/index.php?rid=5593596&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-253 Control of nonlinearity is a challenge in fiber amplifiers designed to generate pulses of a few picoseconds duration, and as a result, picosecond fiber amplifiers have failed to reach peak power of 1MW. Divided-pulse amplification, combined with the use of circular polarization, allows the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593596 Fri, 13 Jan 2012 05:00:00 +0100 5593596 Streak camera crosstalk reduction using a multiple delay optical fiber bundle http://www.medworm.com/index.php?rid=5593595&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-250 The streak camera is one of the fastest photodetection systems, while its capability of multiplexing is particularly attractive to many applications requiring parallel data acquisition. The degree of multiplexing in a streak camera is limited by the crosstalk between input channels. We developed a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593595 Fri, 13 Jan 2012 05:00:00 +0100 5593595 Surface-plasmon-polaritons-assisted nanolithography with dual-wavelength illumination for high exposure depth http://www.medworm.com/index.php?rid=5593594&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-247 We propose a new direct writing nanolithography approach using a plasmonic focusing device and a nano silver mirror with dual-wavelength illumination for high exposure depth. Arrays of pyramid aperture are used to focus the incident light beams into 80 nm light spots. The pyramid combined with a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593594 Fri, 13 Jan 2012 05:00:00 +0100 5593594 Guided-wave second harmonics in Nd:YCOB optical waveguides for integrated green lasers http://www.medworm.com/index.php?rid=5593593&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-244 We report on guided-wave second-harmonic generations in nonlinear Nd:YCa_4O(BO_3)_3 (Nd:YCOB) optical waveguides that are produced by the low-fluence swift Ar^8+ ion irradiation. The guided-wave second harmonics are realized through the frequency doubling and the self-frequency-doubling of the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593593 Fri, 13 Jan 2012 05:00:00 +0100 5593593 Temporal contrast enhancement of picosecond pulses based on phase-conjugate wave generation http://www.medworm.com/index.php?rid=5593592&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-241 A practical technique based on the phase-conjugate wave (PCW) generation is proposed to improve the temporal contrast of the picosecond pulses. Our theory predicts the temporal contrast of the picosecond pulses can be enhanced to about the cube of the temporal contrast of the input pulse via the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593592 Fri, 13 Jan 2012 05:00:00 +0100 5593592 Efficient generation of isolated attosecond pulses with high beam quality by two-color Bessel–Gauss beams http://www.medworm.com/index.php?rid=5593591&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-238 The generation of isolated attosecond pulses with high efficiency and high beam quality is essential for attosecond spectroscopy. We numerically investigate the supercontinuum generation in a neutral rare-gas medium driven by a two-color Bessel–Gauss beam. The results show that an efficient ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593591 Fri, 13 Jan 2012 05:00:00 +0100 5593591 Multiple color reflection in a single unit cell using double-layer electrochromic reaction http://www.medworm.com/index.php?rid=5593590&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-235 Multiple color states have been realized in single unit cell using double electrochromic (EC) reaction. The precise control of bistability in EC compounds which can maintain several colors on the two separated electrodes allows this new type of pixel to be realized. The specific electrical driving ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593590 Fri, 13 Jan 2012 05:00:00 +0100 5593590 Coupling loss minimization of slow light slotted photonic crystal waveguides using mode matching with continuous group index perturbation http://www.medworm.com/index.php?rid=5593589&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-232 We experimentally demonstrate highly efficient coupling into a slow light slotted photonic crystal waveguide. With optical mode converters and group index tapers that provide good optical mode matching and impedance matching, a nearly flat transmission over the entire guided mode spectrum of 68.8 ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593589 Fri, 13 Jan 2012 05:00:00 +0100 5593589 High-spatial-resolution one-dimensional rotational coherent anti-Stokes Raman spectroscopy imaging using counterpropagating beams http://www.medworm.com/index.php?rid=5593588&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-229 A counterpropagating phase-matching geometry is employed for high-spatial-resolution one-dimensional (1D) imaging of temperature and O_2-to-N_2 concentration ratio using picosecond pure-rotational coherent anti-Stokes Raman spectroscopy (RCARS) over a large field (20 mm). A single-shot 1D RCARS ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593588 Fri, 13 Jan 2012 05:00:00 +0100 5593588 Polarization-dependent ablation of silicon using tightly focused femtosecond laser vortex pulses http://www.medworm.com/index.php?rid=5593587&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-226 We demonstrate experimentally that, in a tight focusing geometry, circularly polarized femtosecond laser vortex pulses ablate material differently depending on the handedness of light. This effect offers an additional degree of freedom to control the shape and size of laser-machined structures on a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593587 Fri, 13 Jan 2012 05:00:00 +0100 5593587 High-speed wavelength-division multiplexing quantum key distribution system http://www.medworm.com/index.php?rid=5593586&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-223 A high-speed quantum key distribution system was developed with the wavelength-division multiplexing (WDM) technique and dedicated key distillation hardware engines. Two interferometers for encoding and decoding are shared over eight wavelengths to reduce the system’s size, cost, and control ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593586 Fri, 13 Jan 2012 05:00:00 +0100 5593586 Differential and product Mueller matrix decompositions: a formal comparison http://www.medworm.com/index.php?rid=5593585&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-220 It is shown that the Mueller matrix logarithm and the Mueller matrix roots decompositions used for the extraction of the elementary polarization properties of a depolarizing medium, although being computationally different, are formally equivalent, being both based upon the differential ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593585 Fri, 13 Jan 2012 05:00:00 +0100 5593585 Terahertz tomography using quantum-cascade lasers http://www.medworm.com/index.php?rid=5593623&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-217 The interfaces of a dielectric sample are resolved in reflection geometry using light from a frequency agile array of terahertz quantum-cascade lasers. The terahertz source is a 10-element linear array of third-order distributed-feedback QCLs ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593623 Thu, 12 Jan 2012 05:00:00 +0100 5593623 Evanescent-wave photoacoustic spectroscopy with optical micro/nano fibers http://www.medworm.com/index.php?rid=5593622&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-214 We demonstrate gas detection based on evanescent-wave photoacoustic (PA) spectroscopy with tapered optical fibers. Evanescent-field instead of open-path absorption is exploited for PA generation, and a quartz tuning fork is used for PA detection. A tapered optical fiber with a diameter down to the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593622 Thu, 12 Jan 2012 05:00:00 +0100 5593622 Effective control of photoluminescence from ZnO nanowires by a-SiN_x:H decoration http://www.medworm.com/index.php?rid=5593621&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-211 The a-SiN_x:H with a large bandgap of 3.8 eV was utilized to decorate ZnO nanowires. The UV emission from the a-SiN_x:H-decorated ZnO nanowires are greatly enhanced compared with the undecorated ZnO nanowire. The deep-level defect emission has been completely suppressed even though the sample was ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593621 Thu, 12 Jan 2012 05:00:00 +0100 5593621 Tailored pulse sequences from an 880 nm pumped Nd:YVO_4 bounce amplifier http://www.medworm.com/index.php?rid=5593620&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-208 We report on an 880 nm quasi-continuously pumped Nd:YVO_4 grazing-incidence “bounce” amplifier, operating at a 300 Hz repetition rate. More than 70 dB small signal gain is achieved with a single crystal. Combined with fast programmable modulators, high-contrast and ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593620 Thu, 12 Jan 2012 05:00:00 +0100 5593620 Intense red upconversion luminescence from Tm^3+/Yb^3+ codoped transparent glass ceramic http://www.medworm.com/index.php?rid=5593619&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-205 Tm^3+/Yb^3+ codoped transparent glass ceramic containing β-PbF_2 nanocrystals was successfully prepared. After thermal treatment, emissions from the ^1G_4 state of Tm^3+ excited by 980 nm laser were greatly quenched by cross relaxation ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593619 Thu, 12 Jan 2012 05:00:00 +0100 5593619 High precision micro-displacement fiber sensor through a suspended-core Sagnac interferometer http://www.medworm.com/index.php?rid=5593618&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-202 A sensing system for micro-displacement measurement based in a suspended-core fiber Sagnac interferometer is presented. The suspended-core fiber characterization was made through the use of an optical backscatter reflectometer, screening its multimodal and birefringent behavior. Its sensitivity to ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593618 Thu, 12 Jan 2012 05:00:00 +0100 5593618 Quantitative surface normal measurement by a wavefront camera http://www.medworm.com/index.php?rid=5593617&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-199 A compact wavefront camera that allows users to quantitatively measure the intensity and wavefront at a remote object plane is reported. The camera is built from a chip-scale wavefront sensor that we previously developed. By measuring the wavefront of the image and calibrating the wavefront ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593617 Thu, 12 Jan 2012 05:00:00 +0100 5593617 Wideband tunable laser phase noise reduction using single sideband modulation in an electro-optical feed-forward scheme http://www.medworm.com/index.php?rid=5593616&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-196 A wideband laser phase noise reduction scheme is introduced where the optical field of a laser is single sideband modulated with an electrical signal containing the discriminated phase noise of the laser. The proof-of-concept experiments on a commercially available 1549 nm distributed feedback ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593616 Thu, 12 Jan 2012 05:00:00 +0100 5593616 Perfectly notched long-period fiber grating filter based on ICP dry etching technique http://www.medworm.com/index.php?rid=5593615&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-193 This study presents a new process using inductively a coupled plasma dry etching method to manufacture a long-period fiber grating filter with exact period, vertical sidewalls, and smooth etched surfaces, and the filter is thus named a perfectly notched long-period fiber grating (NLPFG). This ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593615 Thu, 12 Jan 2012 05:00:00 +0100 5593615 Periodic nanostructures on Si(100) surfaces generated by high-repetition rate sub-15 fs pulsed near-infrared laser light http://www.medworm.com/index.php?rid=5593614&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-190 Nanoscale rifts and ripples at a periodicity of 130 nm were generated on Si(100) surfaces immersed in water using tightly focused 800 nm 12 fs pulsed 85 MHz laser light at subnanojoule pulse energies. At radiant exposure close to the ablation threshold rifts were typically 20–50 nm in width ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593614 Thu, 12 Jan 2012 05:00:00 +0100 5593614 Asynchronous midinfrared ultrafast optical parametric oscillator for dual-comb spectroscopy http://www.medworm.com/index.php?rid=5593613&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-187 Two asynchronous, broadband 3.3 µm pulse trains with a stabilized repetition-rate difference of up to 5 kHz were generated using an ultrafast optical parametric oscillator. The two oscillation channels, each producing ∼100??mW average power, ran essentially independently, and weak ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593613 Thu, 12 Jan 2012 05:00:00 +0100 5593613 Twist phase-induced reduction in scintillation of a partially coherent beam in turbulent atmosphere http://www.medworm.com/index.php?rid=5593612&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-184 The scintillation index of a Gaussian Schell-model beam with twist phase (i.e., twisted GSM beam) in weak turbulent atmosphere is formulated with the help of a tensor method. Variations of the scintillation index of a twisted GSM beam on propagation in turbulent atmosphere are studied in detail. It ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593612 Thu, 12 Jan 2012 05:00:00 +0100 5593612 Photonic generation of stable microwave signals from a dual-wavelength Al_2O_3:Yb^3+ distributed-feedback waveguide laser http://www.medworm.com/index.php?rid=5593611&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-181 We report the fabrication and characterization of a dual-wavelength distributed-feedback channel waveguide laser in ytterbium-doped aluminum oxide. Operation of the device is based on the optical resonances that are induced by two local phase shifts in the distributed-feedback structure. A stable ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593611 Thu, 12 Jan 2012 05:00:00 +0100 5593611 Beam tracing approach of 2×2 extended Jones matrix method for stratified uniaxial structures http://www.medworm.com/index.php?rid=5593610&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-178 In compliance with the commonly adopted small anisotropy approximation, a beam tracing modeling of a 2×2 extended Jones matrix algorithm is proposed, which traces the phase retardation along the geometric beam path, instead of along the normal direction, as the light beam is propagating ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593610 Thu, 12 Jan 2012 05:00:00 +0100 5593610 Impact of slow gain dynamics on soliton molecules in mode-locked fiber lasers http://www.medworm.com/index.php?rid=5593609&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-175 We theoretically demonstrate and experimentally confirm the major influence of gain dynamics on soliton molecules that self-assemble in mode-locked lasers. Both slow gain recovery and depletion play a pivotal role in the formation of chirped soliton molecules characterized by an increasing ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593609 Thu, 12 Jan 2012 05:00:00 +0100 5593609 Deterministic qubit transfer between orbital and spin angular momentum of single photons http://www.medworm.com/index.php?rid=5593608&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-172 In this work we experimentally implement a deterministic transfer of a generic qubit initially encoded in the orbital angular momentum of a single-photon to its polarization. Such a transfer of quantum information, which is completely reversible, has been implemented adopting an electrically ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593608 Thu, 12 Jan 2012 05:00:00 +0100 5593608 Coherent-mode representation of supercontinuum http://www.medworm.com/index.php?rid=5593607&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-169 We apply the coherent-mode expansion to correlation functions used to describe the coherence properties of supercontinuum generated in nonlinear fibers. We show that the leading term of the expansion represents the quasi-coherent part of the field while the quasi-stationary part is ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5593607 Thu, 12 Jan 2012 05:00:00 +0100 5593607 Brillouin-assisted microwave frequency measurement with adjustable measurement range and resolution http://www.medworm.com/index.php?rid=5576996&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-166 We present a reconfigurable microwave frequency measurement technique with adjustable measurement range and resolution. The key novelty of the technique is the employment of stimulated Brillouin scattering, which results in a tunable amplitude comparison function, leading to an adjustable ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5576996 Tue, 10 Jan 2012 05:00:00 +0100 5576996 Toward single-molecule detection with sensors based on propagating surface plasmons http://www.medworm.com/index.php?rid=5576995&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-163 Surface plasmon resonance (SPR) sensors are known to be able to detect very low surface concentrations of (bio)molecules on macroscopic areas. To explore the potential of SPR biosensors to achieve single-molecule detection, we have minimized the read-out area (to ∼64??μm^2) by ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5576995 Tue, 10 Jan 2012 05:00:00 +0100 5576995 Wavelength separation from extreme ultraviolet mirrors using phaseshift reflection http://www.medworm.com/index.php?rid=5576994&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-160 A generic design and fabrication scheme of Mo/Si multilayer-grating phaseshift reflector systems is reported. Close to optimized extreme ultraviolet (EUV, λ=13.5??nm) reflectance values up to 64% are demonstrated, while the diffractive properties can be exploited in spectral filtering ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5576994 Tue, 10 Jan 2012 05:00:00 +0100 5576994 Plasmonic properties of aluminum nanorings generated by double patterning http://www.medworm.com/index.php?rid=5576993&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-157 In this Letter we evaluate a technique for the efficient and flexible generation of aluminum nanorings based on double patterning and variable shaped electron beam lithography. The process is demonstrated by realizing nanorings with diameters down to 90 nm and feature sizes of 30 nm utilizing a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5576993 Tue, 10 Jan 2012 05:00:00 +0100 5576993 Experimental demonstration of terahertz metamaterial absorbers with a broad and flat high absorption band http://www.medworm.com/index.php?rid=5576992&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-154 We present the design, numerical simulations and experimental measurements of terahertz metamaterial absorbers with a broad and flat absorption top over a wide incidence angle range for either transverse electric or transverse magnetic polarization depending on the incident direction. The ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5576992 Tue, 10 Jan 2012 05:00:00 +0100 5576992 Phase correlations and optical coherence http://www.medworm.com/index.php?rid=5569241&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-151 We examine the properties of the recently introduced degrees of coherence regarding the phase correlations of the optical field. It is seen that some of these quantities are straightforwardly related to the limits of complete dependence and complete independence of phases, which were used as the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569241 Sat, 07 Jan 2012 07:46:35 +0100 5569241 Spatial-carrier phase-shifting digital holography utilizing spatial frequency analysis for the correction of the phase-shift error http://www.medworm.com/index.php?rid=5569240&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-148 We propose a single-shot digital holography in which the complex amplitude distribution is obtained by spatial-carrier phase-shifting (SCPS) interferometry and the correction of the inherent phase-shift error occurred in this interferometry. The 0th order diffraction wave and the conjugate image ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569240 Sat, 07 Jan 2012 07:46:35 +0100 5569240 Standoff detection of large organic molecules using Rydberg fingerprint spectroscopy and microwave Rayleigh scattering http://www.medworm.com/index.php?rid=5569239&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-145 We present a technique for nonintrusive and standoff detection of large organic molecules using coherent microwave Rayleigh scattering from plasma produced by structure sensitive photoionization through Rydberg states. We test the method on 1,4-diazobicyclooctane. Transitions between the 3s Rydberg ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569239 Sat, 07 Jan 2012 07:46:35 +0100 5569239 Quantum memory in warm rubidium vapor with buffer gas http://www.medworm.com/index.php?rid=5569238&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-142 The realization of quantum memory using warm atomic vapor cells is appealing because of their commercial availability and the perceived reduction in experimental complexity. In spite of the ambiguous results reported in the literature, we demonstrate that quantum memory can be implemented in a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569238 Sat, 07 Jan 2012 07:46:35 +0100 5569238 Three-dimensional study of planar optical antennas made of split-ring architecture outperforming dipole antennas for increased field localization http://www.medworm.com/index.php?rid=5569237&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-139 We report that planar optical antennas made of split-ring architecture are numerically found in three-dimensional simulations to outperform dipole antennas for the enhancement of localized ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569237 Sat, 07 Jan 2012 07:46:35 +0100 5569237 Injection-seeded, gain-switched tunable Cr:ZnSe laser http://www.medworm.com/index.php?rid=5569236&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-136 We report a narrow-linewidth, tunable, gain-switched Cr:ZnSe laser operating between 2255 and 2455 nm. The spectral width of the laser was reduced from 125 nm to 0.3 nm by using injection seeding. Seeding was achieved with a second tunable CW Cr:ZnSe laser. The output wavelength was varied by ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569236 Sat, 07 Jan 2012 07:46:35 +0100 5569236 High-sensitivity Fabry–Perot interferometric pressure sensor based on a nanothick silver diaphragm http://www.medworm.com/index.php?rid=5569235&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-133 We present a fiber-optic extrinsic Fabry–Perot interferometer pressure sensor based on a nanothick silver diaphragm. The sensing diaphragm, with a thickness measured in a few hundreds of nanometers, is fabricated by the electroless plating method, which provides a simple fabrication process ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569235 Sat, 07 Jan 2012 07:46:35 +0100 5569235 Black-light continuum generation in a silica-core photonic crystal fiber http://www.medworm.com/index.php?rid=5569234&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-130 We report the observation of a broadband continuum spanning from 350 to 470 nm in the black-light region of the electromagnetic spectrum as a result of picosecond pumping a solid-core silica photonic crystal fiber at 355 nm. This was achieved despite strong absorption and a large normal dispersion ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569234 Sat, 07 Jan 2012 07:46:35 +0100 5569234 Time-division multiplexing of the orbital angular momentum of light http://www.medworm.com/index.php?rid=5569233&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-127 We present an optical setup for generating a sequence of light pulses in which the orbital angular momentum (OAM) degree of freedom is correlated with the temporal one. The setup is based on a single q plate within a ring optical resonator. By this approach, we demonstrate the generation of a train ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569233 Sat, 07 Jan 2012 07:46:34 +0100 5569233 Omnidirectional emission from top-emitting organic light-emitting devices with microstructured cavity http://www.medworm.com/index.php?rid=5569243&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-124 We demonstrate optimized viewing-angle characteristics from top-emitting organic light-emitting devices by integrating a periodic microstructure into the cavity. A holographic lithography technique combined with filling process of the groove by spin coating of a polymer film has been employed to ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569243 Fri, 06 Jan 2012 05:00:00 +0100 5569243 Long range plasmon assisted all-optical switching at telecommunication wavelengths http://www.medworm.com/index.php?rid=5569242&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-2-121 We exploit the properties of ultranarrow, Fano-like resonances generated by the coupling of long range surface plasmons with ultrathin (∼10?nm), metallic, subwavelength gratings embedded in a nonlinear, cubic material to obtain all-optical switching at telecommunication wavelengths for ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5569242 Fri, 06 Jan 2012 05:00:00 +0100 5569242 Two-photon fluorescence isotropic-single-objective microscopy http://www.medworm.com/index.php?rid=5542389&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-85 Two-photon excitation provides efficient optical sectioning in three-dimensional fluorescence microscopy, independently of a confocal detection. In two-photon laser-scanning microscopy, the image resolution is governed by the volume of the excitation light spot, which is obtained by focusing the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5542389 Mon, 26 Dec 2011 05:00:00 +0100 5542389 Generation of soft x-ray and water window harmonics using a few-cycle, phase-locked, optical parametric chirped-pulse amplifier http://www.medworm.com/index.php?rid=5542396&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-97 Multimillijoule, few-cycle, carrier-envelope-phase (CEP)-locked, near-IR pulses at 750 nm from an optical parametric chirped-pulse amplifier are applied to the generation of CEP-dependent, soft x-ray high harmonics around the boron K-edge at 188 eV. The dependence on the CEP manifests the phase ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5542396 Sat, 24 Dec 2011 05:00:00 +0100 5542396 Optical microresonator based on hollow sphere with porous wall for chemical sensing http://www.medworm.com/index.php?rid=5542395&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-94 A porous-wall hollow glass microsphere (PW-HGM) was investigated as an optical resonator for chemical vapor sensing. A single mode optical fiber taper was used to interrogate the microresonator. Adsorption of chemical molecules into the nanosized pores induced a refractive index change of the thin ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5542395 Sat, 24 Dec 2011 05:00:00 +0100 5542395 Metrology of laser-guided particles in air-filled hollow-core photonic crystal fiber http://www.medworm.com/index.php?rid=5542394&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-91 Micrometer-sized particles are trapped in front of an air-filled hollow-core photonic crystal fiber using a novel dual-beam trap. A backward guided mode produces a divergent beam that diffracts out of the core, and simultaneously a focused laser beam launches a forward-propagating mode into the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5542394 Sat, 24 Dec 2011 05:00:00 +0100 5542394 Improving the optical performance of InGaN light-emitting diodes by altering light reflection and refraction with triangular air prism arrays http://www.medworm.com/index.php?rid=5542393&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-88 The effect of triangular air prism (TAP) arrays with different distance-to-width (d/w) ratios on the enhancement of light extraction efficiency (LEE) of InGaN light-emitting diodes (LEDs) is investigated. The TAP arrays embedded at the sapphire/GaN interface act as light reflectors and refractors, ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5542393 Sat, 24 Dec 2011 05:00:00 +0100 5542393 Wavelength conversion of nanosecond pulses to the mid-IR in photonic crystal fibers http://www.medworm.com/index.php?rid=5542392&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-82 We investigate degenerate four wave mixing with nanosecond pulses in fused silica photonic crystal fibers. Phase-matching curves are calculated taking into account the material and waveguide dispersion. Experiments with a nanosecond pulsed Nd:YAG pump laser and relatively short fiber lengths show ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5542392 Sat, 24 Dec 2011 05:00:00 +0100 5542392 Fundamental structure of Fresnel diffraction: longitudinal uniformity with respect to fractional Fourier order http://www.medworm.com/index.php?rid=5542391&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-103 Fresnel integrals corresponding to different distances can be interpreted as scaled fractional Fourier transformations observed on spherical reference surfaces. Transverse samples can be taken on these surfaces with separation that increases with propagation distance. Here, we are concerned with ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5542391 Sat, 24 Dec 2011 05:00:00 +0100 5542391 Diffraction from carbon nanofiber arrays http://www.medworm.com/index.php?rid=5542390&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-100 A square planar photonic crystal composed of carbon nanofibers was fabricated using e-beam lithography and chemical vapor deposition. The diffraction properties of the system were characterized experimentally and compared with theory and numerical simulations. The intensities of the (−1,0) ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5542390 Sat, 24 Dec 2011 05:00:00 +0100 5542390 Plasmon-enhanced light emission based on lattice resonances of silver nanocylinder arrays http://www.medworm.com/index.php?rid=5533953&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-79 Diffractive arrays of silver nanocylinders are used to increase the radiative efficiency of InGaN/GaN quantum wells emitting at near-green wavelengths. Large enhancements in luminescence intensity (up to a factor of nearly 5) are measured when the array period exceeds the emission wavelength in the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533953 Fri, 23 Dec 2011 14:17:37 +0100 5533953 Instance-based attention: where could humans look first when searching for an object instance http://www.medworm.com/index.php?rid=5533952&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-76 We present an instance-based attention model to predict where humans could look first when searching for an object instance, and we show its application in image synthesis. The proposed model learns configurational rules from vast scene images described by global scene representations. The rules ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533952 Fri, 23 Dec 2011 14:17:37 +0100 5533952 Feasibility of infrared Earth tracking for deep-space optical communications http://www.medworm.com/index.php?rid=5533951&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-73 Infrared (IR) Earth thermal tracking is a viable option for optical communications to distant planet and outer-planetary missions. However, blurring due to finite receiver aperture size distorts IR Earth images in the presence of Earth’s nonuniform thermal emission and limits its ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533951 Fri, 23 Dec 2011 14:17:37 +0100 5533951 Photoreprogrammable dual-function grating based on photochromism and selective metal deposition http://www.medworm.com/index.php?rid=5533950&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-70 We introduce photoreprogrammable dual-function gratings, which show different diffraction in transmission and reflection. Parallel metal lines on the photochromic diarylethene (DAE) surface were prepared by selective metal deposition, enabling one-dimensional diffraction in transmission and ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533950 Fri, 23 Dec 2011 14:17:37 +0100 5533950 Refractive index sensor using microfiber-based Mach–Zehnder interferometer http://www.medworm.com/index.php?rid=5533949&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-67 A simple and robust refractive index (RI) sensor based on a Mach–Zehnder interferometer has been demonstrated. A section of optical microfiber drawn from silica fiber is employed as the sensing arm. Because of the evanescent field, a slight change of the ambient RI will lead to the variation ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533949 Fri, 23 Dec 2011 14:17:37 +0100 5533949 High average power 2 μm generation using an intracavity PPMgLN optical parametric oscillator http://www.medworm.com/index.php?rid=5533948&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-64 An intracavity quasi-phase-matched optical parametric oscillator (OPO) has been developed for the purpose of generating radiation with high average power and high repetition rate in the 2 μm regime. The device is a degenerate OPO based on a 3 mm thick MgO-doped periodically poled LiNbO_3 ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533948 Fri, 23 Dec 2011 14:17:37 +0100 5533948 Solar energy harvesting scheme using syringe-like ZnO nanorod arrays for InGaN/GaN multiple quantum well solar cells http://www.medworm.com/index.php?rid=5533947&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-61 Syringe-like ZnO nanorod arrays (NRAs) synthesized by a hydrothermal method were applied as the light-harvesting layer on InGaN-based multiple quantum well (MQW) solar cells. Theoretical calculations show that the NRAs with an abrupt shrinkage of tip diameter can further suppress surface ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533947 Fri, 23 Dec 2011 14:17:37 +0100 5533947 Slow-light dispersion in periodically patterned silicon microring resonators http://www.medworm.com/index.php?rid=5533946&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-58 We demonstrate a novel periodically patterned ring resonator evanescently coupled with a coupler waveguide (CWG) on a silicon-on-insulator platform. In order to optimize the coupling, we phase match the ring resonator and the CWG by tuning the width of the CWG. In the transmission spectra, we ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533946 Fri, 23 Dec 2011 14:17:37 +0100 5533946 Compact and silicon-on-insulator-compatible hybrid plasmonic TE-pass polarizer http://www.medworm.com/index.php?rid=5533945&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-55 Hybrid plasmonic waveguides consisting of a metal plane separated from a high-index medium by a low-index spacer have recently attracted much interest. Here we show that, by suitably choosing the dimensions and material properties of the hybrid waveguide, a very compact and broadband TE-pass ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533945 Fri, 23 Dec 2011 14:17:37 +0100 5533945 Enhancement of the broadband modulation diffraction efficiency of liquid-crystal displays http://www.medworm.com/index.php?rid=5533970&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-52 We report a method to maximize the broadband modulation diffraction efficiency of liquid-crystal spatial light modulators for polychromatic applications requiring a wide range of wavelengths. An optimized encoding pattern based on the minimum Euclidean projection principle is applied in order to ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533970 Thu, 22 Dec 2011 05:00:00 +0100 5533970 Wavelength tunable laser beam shaping http://www.medworm.com/index.php?rid=5533969&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-49 Laser beam shaping by phase-only transformations, often referred to as field mapping, has for a long time been considered wavelength dependent. In this Letter we outline a simple mathematical argument that shows how the problem may be formulated in a wavelength tunable manner, requiring only a ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533969 Thu, 22 Dec 2011 05:00:00 +0100 5533969 Spinning disk for compressive imaging http://www.medworm.com/index.php?rid=5533968&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-46 We report the first, to the best of our knowledge, experimental implementation of a spinning-disk configuration for high-speed compressive image acquisition. A single rotating mask (i.e., the spinning disk) with random binary patterns was utilized to spatially modulate a collimated terahertz (THz) ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533968 Thu, 22 Dec 2011 05:00:00 +0100 5533968 Normal group-velocity dispersion Kerr frequency comb http://www.medworm.com/index.php?rid=5533967&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-43 We show via numerical simulation that Kerr frequency combs can be generated in a nonlinear resonator characterized with normal group-velocity dispersion. We find the spectral shape of the comb and temporal envelope of the corresponding optical pulses formed in the resonator. (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533967 Thu, 22 Dec 2011 05:00:00 +0100 5533967 Compact all-optical switch for WDM networks based on Raman effect in silicon nanowavegide http://www.medworm.com/index.php?rid=5533966&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-40 We propose an all-optical switching scheme based on Raman gain in a silicon nanowaveguide suitable for multichannel optical communication. Raman gain is used for amplification of a control pulse with a higher wavelength, which depletes the tuned channel signal. Separation between control and signal ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533966 Thu, 22 Dec 2011 05:00:00 +0100 5533966 Continuous-wave Yb-doped Sc_2SiO_5 thin-disk laser http://www.medworm.com/index.php?rid=5533965&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-37 We present in this Letter experimental results of a Yb:Sc_2SiO_5 (Yb:SSO) thin-disk laser. To our knowledge, this is the first lasing demonstration of this crystal in thin-disk configuration reported on to date. Preliminary tests regarding the characterization and the laser operation are presented. ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533965 Thu, 22 Dec 2011 05:00:00 +0100 5533965 Photostability of lasing process from water solution of Rhodamine 6G with gold nanoparticles http://www.medworm.com/index.php?rid=5533964&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-34 We report the lasing performance and photobleaching of gain material containing a water solution of Rhodamine 6G dye and gold nanoparticles (NPs). In comparison to a pure dye solution, the investigated material demonstrated both enhancement and quenching of the lasing output, depending on the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533964 Thu, 22 Dec 2011 05:00:00 +0100 5533964 Efficient and accurate local model for colorimetric characterization of liquid-crystal displays http://www.medworm.com/index.php?rid=5533963&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-31 Taking the chromaticity inconstancy of LCDs and the inverse efficiency into account, a novel local colorimetric characterization model was developed in this Letter. Rather than dividing the device color space into many subspaces to refine the chromaticity description as existent local models, the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533963 Thu, 22 Dec 2011 05:00:00 +0100 5533963 Optical fiber refractometers based on indium tin oxide coatings fabricated by sputtering http://www.medworm.com/index.php?rid=5533962&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-28 This Letter presents the fabrication of optical fiber refractometers based on indium tin oxide (ITO) coatings deposited by sputtering with response in the visible region. ITO thin films have been sputtered by means of a rotating mechanism that enables the fabrication of smooth and homogeneous ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533962 Thu, 22 Dec 2011 05:00:00 +0100 5533962 Grating-based wavelength control of single- and two-color vertical-external-cavity-surface-emitting lasers http://www.medworm.com/index.php?rid=5533961&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-25 Wide wavelength tunability of single- and two-color operating vertical-external-cavity-surface-emitting lasers (VECSELs) is demonstrated. Employing an external feedback based on a diffractive grating outside the cavity of a narrow-line single-color VECSEL allows for a continuous tuning of the ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533961 Thu, 22 Dec 2011 05:00:00 +0100 5533961 Fabrication of optical mosaics mimicking human corneal endothelium for the training and assessment of eye bank technicians http://www.medworm.com/index.php?rid=5533960&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-22 The determination of endothelial cell density (ECD) is a crucial activity in eye banks for the assessment of corneal tissue quality. These cells are responsible for corneal transparency, and ECD correlates with graft survival. ECD is mainly assessed with a manual “naked-eye” procedure ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533960 Thu, 22 Dec 2011 05:00:00 +0100 5533960 Generalization of three-dimensional N-ocular imaging systems under fixed resource constraints http://www.medworm.com/index.php?rid=5533959&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-19 The performance of multiview three-dimensional imaging systems depends on several factors, including the number of sensors, sensor pixel size, relative sensor configuration, imaging optics, and computational reconstruction algorithm. Therefore, it is important to compare the performance of such ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533959 Thu, 22 Dec 2011 05:00:00 +0100 5533959 Photonic approach to the simultaneous measurement of the frequency, amplitude, pulse width, and time of arrival of a microwave signal http://www.medworm.com/index.php?rid=5533958&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-7 A photonic approach to the simultaneous measurement of the frequency, pulse amplitude (PA), pulse width (PW), and time of arrival (TOA) of an unknown pulsed microwave signal is proposed and demonstrated. The measurement is performed based on optical carrier-suppressed modulation, complementary ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533958 Thu, 22 Dec 2011 05:00:00 +0100 5533958 Energy transfer between laser filaments in liquid methanol http://www.medworm.com/index.php?rid=5533957&cid=s_36567_75_f&fid=36567&url=http%3A%2F%2Fwww.opticsinfobase.org%2Fabstract.cfm%3FURI%3Dol-37-1-16 We demonstrate energy exchange between two filament-forming femtosecond laser beams in liquid methanol. Our results are consistent with those of previous works documenting coupling between filaments in air; in addition, we identify an unreported phenomenon in which the direction of energy exchange ... (Source: Optics Letters) Optics Letters journals http://www.medworm.com/rss/comments.php?id=5533957 Thu, 22 Dec 2011 05:00:00 +0100 5533957