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March


A Simple Fully-Reflective Method of Scatter Reduction in 2D-IR Spectroscopy

  • Aaron Massari, Ivan Spector, Courtney Olson, and Christopher Huber
  • received 12/11/2014; accepted 03/25/2015; posted 03/25/2015; Doc. ID 230607
  • [full text: PDF (2201) KB)]
  • Abstract: A fully-reflective two-dimensional IR (2D-IR) setup is described that enables efficient cancelation of scattered light from multiple pulses in the phase matched direction. The signal stimulating and local oscillator pulses are synchronously modulated (or fibrillated) in time maintaining their phase relationships with the echo wavepacket. The modification is cost-effective and can be easily implemented on existing 2D-IR instruments, and it avoids the addition of dispersive elements into the beam paths. The fibrillation results in a decrease of waiting time resolution of only tens of femtoseconds and has no impact on the spectral lineshape, making it a general improvement for 2D-IR spectrometers even for weakly- or non-scattering samples.

Keywords (OCIS):

  • (190.4400) Nonlinear optics : Nonlinear optics, materials
  • (300.2570) Spectroscopy : Four-wave mixing
  • (300.6340) Spectroscopy : Spectroscopy, infrared
  • (320.7100) Ultrafast optics : Ultrafast measurements

Correlations in Pulsed Resonance Fluorescence

  • kumarasiri konthasinghe, Manoj Peiris, Benjamin Petrak, Ying Yu, Zhi-Chuan Niu, and Andreas Muller
  • received 12/04/2014; accepted 03/25/2015; posted 03/26/2015; Doc. ID 228918
  • [full text: PDF (907) KB)]
  • Abstract: We investigated the first and second-order correlations of the light scattered near-resonantly by a quantum dot under excitation by a frequency-comb, i.e., a periodically-pulsed laser source. In contrast to its monochromatic counterpart, the pulsed resonance fluorescence spectrum features a superposition of sidebands distributed around a central peak, with maximal sideband intensity near the Rabi frequency. Distinguishing between the coherently and incoherently scattered light reveals pulse-area dependent Rabi oscillations evolving with different phase for each component. This phase, sensitive to the laser pulse width, introduces an ambiguity in the interpretation of the Rabi cycle. Nevertheless, both first and second-order correlations of the scattered light agree well with theoretical simulations when the effect of spectral diffusion is taken into account.

Keywords (OCIS):

  • (270.0270) Quantum optics : Quantum optics
  • (270.1670) Quantum optics : Coherent optical effects
  • (270.5290) Quantum optics : Photon statistics
  • (270.5565) Quantum optics : Quantum communications

Gaussian beam waist and an extreme property of the beam area

  • Evgeniya Razueva, Alexander Krutov, and Eugeny Abramochkin
  • received 12/09/2014; accepted 03/25/2015; posted 03/26/2015; Doc. ID 229377
  • [full text: PDF (523) KB)]
  • Abstract: We propose a possible generalization of the waist plane for a two-dimensional astigmatic Gaussian beam as a plane of minimal spot area of the beam during propagation. It is shown that the defocusing component of the beam phase vanishes in this plane. Some examples of astigmatic Gaussian beams and corresponding area waist planes are presented and discussed.

Keywords (OCIS):

  • (140.3300) Lasers and laser optics : Laser beam shaping
  • (350.5500) Other areas of optics : Propagation
  • (140.3295) Lasers and laser optics : Laser beam characterization

Complete trapping of electromagnetic radiation using surface magnetoplasmons

  • Xiaohua Deng, Linfang Shen, Wang Zhuoyuan, jin wu, and Tzong-Jer Yang
  • received 12/24/2014; accepted 03/25/2015; posted 03/26/2015; Doc. ID 231391
  • [full text: PDF (828) KB)]
  • Abstract: Because the dispersion properties of surface magnetoplasmons (SMPs) in a magnetized plasmonic material closely depend on its cladding dielectric, it is possible to completely trap SMPs in a system consisting of a plasmonic material with cladding of a dielectric heterostructure. By using a semiconductor in the terahertz regime, we show that one-way SMPs in such a system can be completely trapped at the interface of the heterostructure and that, consequently, a focused subwavelength-scale hotspot is generated, the fields of which are much strongly enhanced. Moreover, a one-way SMP pulse in this system can also be completely trapped, and the wave packet can be compressed into a stable hotspot on the subwavelength scale.

Keywords (OCIS):

  • (210.3810) Optical data storage : Magneto-optic systems
  • (240.6680) Optics at surfaces : Surface plasmons
  • (250.5403) Optoelectronics : Plasmonics

Moiré pattern generation by dual shearing and its modulation by surface plasmon resonance

  • Mina Ray, Mahua Bera, and Jayeta Banerjee
  • received 01/16/2015; accepted 03/25/2015; posted 03/26/2015; Doc. ID 232503
  • [full text: PDF (1428) KB)]
  • Abstract: A novel surface plasmon resonance (SPR) mediated Moiré fringe generation is theoretically and experimentally investigated using a birefringent lens (BL) and a Wollaston prism. Birefringent lens having two longitudinally shifted focal points provides radial shear whereas Wolllaston prism introduces lateral shear between the two radially sheared patterns for mutual orthogonal polarizations. Thus Moiré-like pattern is produced at the overlapping region of those patterns. Brief theory and experimental demonstration of coherent and incoherent Moiré fringe generation by such dual shearing is presented. The appearance and disappearance of Moiré pattern with the rotation of the analyzer axis has also been demonstrated. A modified experimental set-up has also been developed to observe the influence of plasmonic excitation on such patterns which can be further utilized for photonic applications such as sensing and imaging.

Keywords (OCIS):

  • (120.4120) Instrumentation, measurement, and metrology : Moire' techniques
  • (260.1440) Physical optics : Birefringence
  • (250.5403) Optoelectronics : Plasmonics

Coupled-mode induced transparency in aerostatically-tuned microbubble whispering gallery resonators

  • Yong Yang, Sunny Saurabh, Jonathan Ward, and Síle Nic Chormaic
  • received 02/09/2015; accepted 03/25/2015; posted 03/26/2015; Doc. ID 234179
  • [full text: PDF (588) KB)]
  • Abstract: Coupled-mode induced transparency is realized in a single microbubble whispering gallery mode resonator. Using aerostatic tuning, we find that the pressure induced shifting rates are different for different radial order modes. A finite element simulation considering both the strain and stress effects shows a GHz/bar difference and this is confirmed by experiments. A transparency spectrum is obtained when a first order mode shifts across a higher order mode through precise pressure tuning. The resulting lineshapes are fitted with the theory. This work lays a foundation for future applications in microbubble sensing.

Keywords (OCIS):

  • (220.4000) Optical design and fabrication : Microstructure fabrication
  • (230.3990) Optical devices : Micro-optical devices
  • (140.3948) Lasers and laser optics : Microcavity devices
  • (280.4788) Remote sensing and sensors : Optical sensing and sensors
  • (280.5475) Remote sensing and sensors : Pressure measurement

Second-harmonic generation of light at 245 nm in a lithium tetraborate whispering gallery resonator

  • Josef Fürst, L Bohaty, Ingo Breunig, Karsten Buse, Petra Becker, and Josef Liebertz
  • received 02/27/2015; accepted 03/25/2015; posted 03/26/2015; Doc. ID 235320
  • [full text: PDF (1880) KB)]
  • Abstract: A millimeter-sized, monolithic whispering gallery resonator made of a lithium tetraborate, Li₂B₄O₇, crystal was employed for doubly-resonant second-harmonic generation with a continuous-wave laser source at 490 nm. An intrinsic quality factor of 2 × 10⁸ was observed at the pump wavelength. A conversion efficiency of 2.2 % was attained with 5.9 mW of mode-matched pump power. In the lithium tetraborate resonator, it is feasible to achieve phase-matching of second harmonic generation for pump wavelengths between 486 and 506 nm.

Keywords (OCIS):

  • (190.2620) Nonlinear optics : Harmonic generation and mixing
  • (190.4390) Nonlinear optics : Nonlinear optics, integrated optics
  • (230.4320) Optical devices : Nonlinear optical devices
  • (250.4390) Optoelectronics : Nonlinear optics, integrated optics

Super resolution using Barker-based array projected via spatial light modulator

  • Asaf Ilovitsh, Tali Ilovitsh, Eyal Preter, Nadav Levanon, and Zeev Zalevsky
  • received 02/20/2015; accepted 03/24/2015; posted 03/25/2015; Doc. ID 235051
  • [full text: PDF (1173) KB)]
  • Abstract: The use of a two dimensional Barker-based array in the conventional time multiplexing super resolution technique was recently presented [Ilovitsh et al., Opt. Lett. 40(2), 163–165 (2015)]. It enables achieving a two dimensional super resolution image using only one dimensional scan, by exploiting its unique auto correlation property. In this paper we refine the method using a mismatched array for the decoding process. The cross correlation between the Barker-based array and the mismatched array has a perfect peak to sidelobes ratio, making it ideal for the super resolution process. Also, we propose the projection of this array onto the object using a phase-only spatial light modulator. Projecting the array eliminates the need for printing it, mechanically shifting it, and having a direct contact with the object, which is not feasible in many imaging applications. 13 phase masks, which generate shifted Barker-based arrays, were designed using a revised Gerchberg-Saxton algorithm. A sequence of 13 low resolution images were captured using these phase masks, and were decoded using the mismatched arrays, resulting with a high resolution image. The proposed mismatched array and the design process of the phase masks are presented, and the method is validated by a laboratory experiment.

Keywords (OCIS):

  • (100.0100) Image processing : Image processing
  • (100.5090) Image processing : Phase-only filters
  • (100.6640) Image processing : Superresolution
  • (070.6120) Fourier optics and signal processing : Spatial light modulators

Condition for unity absorption in an ultrathin and highly-lossy film in a Gires-Tournois interferometer configuration

  • Junghyun Park, Mark Brongersma, and Soo Jin Kim
  • received 01/29/2015; accepted 03/24/2015; posted 03/26/2015; Doc. ID 233424
  • [full text: PDF (431) KB)]
  • Abstract: We present a condition for unity absorption for a Gires-Tournois interferometer configuration constructed from an ultrathin and highly-lossy film on top of metallic mirror. From the impedance matching condition in the transmission line theory, we identify a solution space for the required complex refractive index of the lossy film in various film thickness and dielectric constants of the metallic mirror. It is shown that strong absorption requires the imaginary part of the refractive index of the ultrathin lossy film be larger than 0.64, and the physical origin of this condition is elucidated. The proposed method is useful in identifying candidate semiconductor materials that can be used as the lossy film in a unity-absorption Gires-Tournois interferometer configuration and designing the thickness of this film to maximize absorption.

Keywords (OCIS):

  • (230.5160) Optical devices : Photodetectors
  • (230.5750) Optical devices : Resonators
  • (310.6870) Thin films : Thin films, other properties
  • (310.3915) Thin films : Metallic, opaque, and absorbing coatings
  • (310.6805) Thin films : Theory and design
  • (310.6845) Thin films : Thin film devices and applications

Improved Performance of Thermal-Optic Switch with Polymer/Silica Hybrid and Air Trench Waveguide Structures

  • Xibin Wang, Yu-Fen Liu, Jing-Wen Sun, Jian Sun, Fei Wang, Changming Chen, Xiaoqiang Sun, Zhanchen Cui, and Da-Ming Zhang
  • received 02/04/2015; accepted 03/24/2015; posted 03/26/2015; Doc. ID 234001
  • [full text: PDF (1006) KB)]
  • Abstract: By exploiting the polymer/silica hybrid and the air trench waveguide structures, we demonstrate a new type of low-power consuming and high-speed thermal-optic (TO) switch. Such a design provides an effective means to shorten the switching time of the TO switches, as well as to reduce the power consumption at the same time. This TO switch operated with less than 150 µs of switching time via a polymer/silica hybrid waveguide structure. Meanwhile, the power consumption was reduced to be 3.4 mW by introducing the air trench structure.

Keywords (OCIS):

  • (130.0130) Integrated optics : Integrated optics
  • (160.6840) Materials : Thermo-optical materials
  • (230.7390) Optical devices : Waveguides, planar
  • (130.4815) Integrated optics : Optical switching devices

Multi-resonant optical parametric oscillator based on 2D-PPLT nonlinear photonic crystal

  • Mohamed LAZOUL, Azzedine Boudrioua, Lotfy Simohamed, and Lung-Han Peng
  • received 01/26/2015; accepted 03/24/2015; posted 03/25/2015; Doc. ID 233242
  • [full text: PDF (412) KB)]
  • Abstract: The aim behind this work is to achieve an optical parametric oscillator based on 2D-PPLT crystals that are designed to allow multiple reciprocal lattice vectors contribution to the quasi-phase matching scheme. We are particularly interested in the effect of the multi-wavelength parametric generation performed by the 2D nonlinear photonic crystal to achieve a multi-resonant optical parametric oscillator. The performances are studied in terms of generation efficiency and multi-wavelength generation.

Keywords (OCIS):

  • (190.4970) Nonlinear optics : Parametric oscillators and amplifiers
  • (160.5298) Materials : Photonic crystals

Broadband and fabrication-tolerant on-chip scalable mode-division multiplexing based on mode-evolution counter-tapered couplers

  • Fuwan Gan, Jing Wang, Yi Xuan, Minghao Qi, Haiyang Huang, You Li, Ming Li, Xin Chen, Zhen Sheng, Aimin Wu, Wei Li, Xi Wang, and Shichang Zou
  • received 01/27/2015; accepted 03/24/2015; posted 03/25/2015; Doc. ID 233256
  • [full text: PDF (3852) KB)]
  • Abstract: A broadband and fabrication-tolerant on-chip scalable mode-division multiplexing (MDM) scheme based on mode-evolution counter-tapered couplers is designed and experimentally demonstrated in silicon-on-insulator (SOI) platforms. Owing to the broadband advantages of mode evolution, the two-mode MDM link exhibits a very large -1 dB bandwidth of > 180 nm, which is considerably better than most of the previously-reported MDM links no matter they are based on mode-interference or evolution to the best of our knowledge. In addition, the performances remain stable even for a large device width variation from -60 nm to 40 nm. This MDM scheme can be easily extended to higher-order mode multiplexing and a three-mode MDM link is measured with < -10 dB crosstalk from 1.46 μm to 1.64 μm wavelength range.

Keywords (OCIS):

  • (030.4070) Coherence and statistical optics : Modes
  • (060.4230) Fiber optics and optical communications : Multiplexing
  • (130.3120) Integrated optics : Integrated optics devices
  • (230.7370) Optical devices : Waveguides

Cancellation of non-conservative scattering forces in optical traps by counter-propagating beams

  • Lukas Novotny, Shawn Divitt, and Loic Rondin
  • received 01/29/2015; accepted 03/23/2015; posted 03/24/2015; Doc. ID 233503
  • [full text: PDF (1250) KB)]
  • Abstract: Non-conservative forces in optical tweezers generate undesirable behavior such as particle loss due to radiation pressure and preclusion of thermodynamic equilibrium. Here, we rigorously derive criteria for elimination of non-conservative forces and describe how these criteria can be met by a large class of counter-propagating, focused optical beams.

Keywords (OCIS):

  • (020.7010) Atomic and molecular physics : Laser trapping
  • (030.1640) Coherence and statistical optics : Coherence
  • (350.4855) Other areas of optics : Optical tweezers or optical manipulation

Controllable near-field intensity and spot size of hybrid terahertz metamaterial

  • Changhong Chen, Dejia Meng, Md Nadim Ferdous Hoque, Wei Wang, Zhaoyang Fan, Kejia Wang, and Jianjun Lai
  • received 03/04/2015; accepted 03/23/2015; posted 03/24/2015; Doc. ID 235576
  • [full text: PDF (1688) KB)]
  • Abstract: We report controllable near fields around split-ring resonator (SRR) gaps of an active terahertz metamaterial. As extension of parallel-plate capacitors, patterned VO2 is integrated into the metallic SRRs to manipulate the near-field intensity and hot spot size through its metal-insulator transition. This design enhances the device reliability by preventing VO2 dielectric breakdown at a strongly enhanced near field. The near-field intensity and spot size are tunable in broad ranges, and the device is demonstrated to be capable of compensating resonant frequency drift arisen from different interactions due to near-field coupling. It provides an effective method to actively manipulate the light-matter interaction through the strongly enhanced and tunable near fields.

Keywords (OCIS):

  • (240.6680) Optics at surfaces : Surface plasmons
  • (300.6495) Spectroscopy : Spectroscopy, teraherz
  • (310.6628) Thin films : Subwavelength structures, nanostructures

Power transfer mechanism of metallic grating coupled whispering gallery microsphere resonator

  • Yanyan Zhou, Bobo Gu, Chen Zhao, Xia Yu, Feng Luan, and Wei Ding
  • received 01/12/2015; accepted 03/23/2015; posted 03/25/2015; Doc. ID 223354
  • [full text: PDF (650) KB)]
  • Abstract: Power transfer mechanism of the Fano resonance in a metallic grating coupled whispering gallery microsphere resonator is both theoretically investigated and experimentally verified. Based on temporal coupled mode theory, a two-stage cascaded scattering model is formulated to account for the power interaction of multiple resonances in the system. The modeled results show agreement with experimental measurements and are able to explain several counter-intuitive observations in the spectra. Coupling efficiency of the grating coupler is evaluated at critical coupling by approximating symmetric resonance line-shape with grating design. Based on the modelled results, it is found that the coupling efficiency can be further improved by enhancing diffraction efficiency of the first-order diffractions.

Keywords (OCIS):

  • (050.1950) Diffraction and gratings : Diffraction gratings
  • (060.2310) Fiber optics and optical communications : Fiber optics
  • (140.3945) Lasers and laser optics : Microcavities

Mapping transverse velocity of particles in capillary vessels by time-varying laser speckle through perturbation analyses

  • Yi Wang, Ruikang Wang, and Zhenhe Ma
  • received 11/26/2014; accepted 03/23/2015; posted 03/24/2015; Doc. ID 228285
  • [full text: PDF (586) KB)]
  • Abstract: We propose a cross-correlation method to map the transverse velocities of particles moving in capillary vessels using full-field time-varying laser speckle technique. The mapping is achieved by a semi-random perturbation model that describes the intensity fluctuation of time-varying laser speckle signals. When passing through probing volume, moving particles encode a random perturbation into the observed laser speckle pattern. We calculate the transverse flow velocity by cross-correlating the temporal envelopes of the perturbation signals. The proposed method is experimentally verified by the use of polymer microsphere suspension in a glass capillary.

Keywords (OCIS):

  • (170.3880) Medical optics and biotechnology : Medical and biological imaging
  • (170.4470) Medical optics and biotechnology : Ophthalmology
  • (170.6480) Medical optics and biotechnology : Spectroscopy, speckle

Limits to the information gain from lidar measurements

  • Aniceto Belmonte
  • received 12/03/2014; accepted 03/23/2015; posted 03/24/2015; Doc. ID 229014
  • [full text: PDF (408) KB)]
  • Abstract: Measurements over the return signal are an integral part of lidar remote sensing by which we gather information about the characteristics of specific targets. But how much information is gained by performing a given lidar measurement? By defining Shannon’s mutual information of a lidar observation, here we consider the bits of information content on the measurement and describe mathematically the capacity of lidar estimates to represent a corresponding property in the target. For heterodyne Doppler lidars in particular, we have found simple analytical formulas that considers the information gain in mean-frequency estimates.

Keywords (OCIS):

  • (010.0010) Atmospheric and oceanic optics : Atmospheric and oceanic optics
  • (010.3640) Atmospheric and oceanic optics : Lidar
  • (170.3880) Medical optics and biotechnology : Medical and biological imaging
  • (110.3055) Imaging systems : Information theoretical analysis
  • (280.4788) Remote sensing and sensors : Optical sensing and sensors

Flat-panel see-through three-dimensional display based on integral imaging

  • Yasuhiro Takaki and Yuta Yamaguchi
  • received 12/22/2014; accepted 03/23/2015; posted 03/24/2015; Doc. ID 231253
  • [full text: PDF (12109) KB)]
  • Abstract: This study proposes a technique to construct a flat-panel see-through three-dimensional (3D) display based on integral imaging. This display consists of multiple lens arrays, a transparent flat-panel display, and a light blocking wall (LBW). Rays behind the display are reconstructed in front of it by combination of the lens arrays and the LBW to provide the see-through function. The combination of one of the lens arrays and the transparent flat-panel display produces full-parallax 3D images, which are superimposed on background images. The experimental system is constructed to verify the proposed technique. The see-through and superposition capabilities of the experimental system are demonstrated.

Keywords (OCIS):

  • (110.0110) Imaging systems : Imaging systems
  • (120.2040) Instrumentation, measurement, and metrology : Displays

Optical Binding in White Light

  • Shai Maayani, Tal Carmon, and Leopoldo Martín
  • received 01/05/2015; accepted 03/23/2015; posted 03/24/2015; Doc. ID 231466
  • [full text: PDF (2009) KB)]
  • Abstract: We experimentally report on an incoherent light beam that traps multi-aerosols. The trapped particles are levitating in air forming an optomechanical system that does not suffer from material loss. We report here, for the first time, on 3D White-light binding of particles with a variety of sizes and shapes, while long-range interacting at the underdamped regime. Incoherency allows mitigation of interference fringes to enable monotonically changing the distance between particles from 60 micron to touching - constituting a parametrically controlled testbed for transition studies at new scales.

Keywords (OCIS):

  • (220.4880) Optical design and fabrication : Optomechanics
  • (350.4855) Other areas of optics : Optical tweezers or optical manipulation

Polarization nonreciprocity suppression of dual-polarization fiber-optic gyroscope under temperature variation

  • Chao Peng, Ping Lu, Zinan Wang, Rongya Luo, Dayu Zhao, and Li Zhengbin
  • received 01/08/2015; accepted 03/23/2015; posted 03/24/2015; Doc. ID 232020
  • [full text: PDF (738) KB)]
  • Abstract: Polarization nonreciprocity (PN) is one of the most critical factors that degrades the performance of interferometric fiber-optic gyroscope (IFOG), particularly under varying temperature. We present an experimental investigation of PN error suppression in a dual-polarization IFOG. Both experimental results and theoretical analysis indicate that the PN errors of the two orthogonal polarized light always have opposite signs that can be effectively compensated despite the temperature variation. As a result, the long-term stability of the IFOG has been significantly improved. This study is promising for reducing the temperature fragility of IFOGs.

Keywords (OCIS):

  • (060.2370) Fiber optics and optical communications : Fiber optics sensors
  • (060.2800) Fiber optics and optical communications : Gyroscopes

Articles 1 to 20 of 80 Next Page >>





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