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Articles 1 to 20 of 88 Next Page >>

November


Continuous-wave anti-Stokes Raman laser based on phase-matched nondegenerate four-wave mixing

  • Shin-ichi Zaitsu and Totaro Imasaka
  • received 10/01/2014; accepted 11/20/2014; posted 11/20/2014; Doc. ID 223637
  • [full text: PDF (529) KB)]
  • Abstract: We demonstrate phase-matched nondegenerate four-wave mixing in a high-finesse optical cavity using a gaseous Raman-active medium pumped by two independent continuous-wave lasers. Efficient upconversion is achieved for pump beams at different wavelengths under phase-matched conditions by optimizing the total dispersion of the hydrogen-filled optical cavity. The independent control of the pump-beam polarizations leads to further enhancement of the upconversion efficiency arising from a larger Raman gain than that in degenerate four-wave mixing. This approach offers a promising alternative for a narrow-linewidth tunable light source for highly precise laser spectroscopy.

Keywords (OCIS):

  • (140.3550) Lasers and laser optics : Lasers, Raman
  • (190.4380) Nonlinear optics : Nonlinear optics, four-wave mixing

Ultra-compact channel drop fifilter based on photonic crystal nanobeam cavities utilizing a resonant tunneling effect

  • Yaocheng Shi, Xiaochen Ge, and Sailing He
  • received 10/13/2014; accepted 11/20/2014; posted 11/20/2014; Doc. ID 224854
  • [full text: PDF (1760) KB)]
  • Abstract: The design, fabrication and characterization of a compact photonic crystal nanobeam drop filter based on the tunneling effect of the degenerate modes are presented. The accidental degeneracy was achieved by tuning the coupling distance between the nanobeam and input/output waveguides. The tunneling effect of degenerate resonances with different symmetries has been verified experimentally. Channel drop filters with an extinction ratio larger than 10 dB and a quality factor of ~5000 have been experimentally demonstrated.

Keywords (OCIS):

  • (230.5298) Optical devices : Photonic crystals
  • (230.7408) Optical devices : Wavelength filtering devices

Graphene plasmons propagation on corrugated silicon substrates

  • Qing Dai, Xiang-Tian Kong, and Bing Bai
  • received 10/20/2014; accepted 11/20/2014; posted 11/20/2014; Doc. ID 225144
  • [full text: PDF (383) KB)]
  • Abstract: The configuration of graphene on a silicon substrate is potentially compatible to the microelectronic technology. But the maintained plasmons have significant ohmic losses because of silicon's large permittivity. We propose to introduce air grooves in the silicon surface to reduce the optical thickness of silicon and hence decrease the propagation loss. The properties of graphene plasmons on the corrugated silicon substrates are numerically investigated, in terms of the photon frequency and the geometrical parameters of the corrugated layer. The propagation length of the plasmons on corrugated silicon substrates can reach more than twice of that on flat silicon in a broadband in mid-infrared. This study may be useful for designing graphene-based plasmonic waveguides for future applications of photonic integrated circuits.

Keywords (OCIS):

  • (230.7370) Optical devices : Waveguides
  • (240.6680) Optics at surfaces : Surface plasmons
  • (050.6624) Diffraction and gratings : Subwavelength structures

Silicon hybrid demultiplexer with 64 channels for wavelength/mode-division multiplexed on-chip optical interconnects

  • Daoxin Dai, Jian Wang, and Sitao Chen
  • received 10/13/2014; accepted 11/19/2014; posted 11/20/2014; Doc. ID 224844
  • [full text: PDF (1607) KB)]
  • Abstract: A 64-channel hybrid demultiplexer based on silicon-on-insulator nanowires is demonstrated experimentally to enable wavelength-division-multiplexing and mode-division-multiplexing simultaneously for realizing an ultra-large capacity optical-interconnect link. The present hybrid demultiplexer consists of a 4-channel mode multiplexer realized with three cascaded asymmetrical directional-couplers and four identical arrayed-waveguide gratings (AWGs) with 16 channels. For the fabricated hybrid multiplexer, the excess loss and the crosstalk are about -7dB and -10dB, respectively. Better performances can be achieved by minimizing the imperfections (particularly in AWGs) during the fabrication processes. The present hybrid demultiplexer is scalable to have more channels by utilizing more wavelengths, modes and even polarizations.

Keywords (OCIS):

  • (060.4230) Fiber optics and optical communications : Multiplexing
  • (130.3120) Integrated optics : Integrated optics devices
  • (230.7408) Optical devices : Wavelength filtering devices

Nonlinear diffraction from high order Hermite-Gauss beams

  • Ksawery Kalinowski, Ady Arie, Asia Shapira, and Ana Libster-Hershko
  • received 10/23/2014; accepted 11/19/2014; posted 11/20/2014; Doc. ID 225457
  • [full text: PDF (5284) KB)]
  • Abstract: We investigate experimentally and theoretically the nonlinearly diffracted second harmonic light from the first order Hermite-Gauss beam. We investigate the cases of loosely and tightly focused beams in a periodically poled lithium niobate crystal in the temperature range near the birefringent phase matching. Unlike the case of fundamental Gaussian beam, the nonlinear diffracted beam is spatially structured. Its shape depends on the focusing conditions and on the crystal temperature. Furthermore, for the case of tight focusing, the diffracted beam structure depends on the beam's position with respect to the domain wall.

Keywords (OCIS):

  • (190.0190) Nonlinear optics : Nonlinear optics
  • (190.4410) Nonlinear optics : Nonlinear optics, parametric processes
  • (190.4420) Nonlinear optics : Nonlinear optics, transverse effects in
  • (190.4223) Nonlinear optics : Nonlinear wave mixing

Reconfigurable dual-channel dropping filters based on a self coupled resonator Sagnac interferometer

  • Xuenan Zhang, Yundong Zhang, Xiaoqi Liu, Kaiyang Wang, Chi Xu, Yongfeng Wu, and Ping Yuan
  • received 09/24/2014; accepted 11/19/2014; posted 11/20/2014; Doc. ID 223778
  • [full text: PDF (900) KB)]
  • Abstract: We report a reconfigurable dual-mode resonator based dual-channel dropping filter (DRDDF) in a self coupled resonator Sagnac interferometer (SCRSNI). The dual dropping channels are generated within a free spectral range (FSR) via the interference between the electromagnetically induced transparency (EIT)-like and electromagnetically induced absorption (EIA)-like resonances despite only one resonator used in the DRDDF. Depending on the phase tuning, the reconfiguration of the dual channels enabling the truly on/off switching mechanism is realized, and the output modes resembling the add/drop/neutral states are provided. The compact, reliable, flexible, versatile, and extendable DRDDF has profound implications for wavelength division multiplexing (WDM) applications in optical interconnection networks.

Keywords (OCIS):

  • (130.3120) Integrated optics : Integrated optics devices
  • (230.5750) Optical devices : Resonators
  • (230.4555) Optical devices : Coupled resonators
  • (130.4815) Integrated optics : Optical switching devices
  • (130.7408) Integrated optics : Wavelength filtering devices

Precise Evaluation of the Helholtz Equation for Optical Propagation

  • George Sutton and John Pond
  • received 07/28/2014; accepted 11/19/2014; posted 11/20/2014; Doc. ID 209304
  • [full text: PDF (612) KB)]
  • Abstract: The Helmholtz equation for electromagnetic propagation has been numerically evaluated with no approximations or linearization using a 64 bit processor, for a uniform monochromatic beam from a circular aperture, permitting very large values of the ratio of the aperture size to the wavelength, ~105. The multiple spots of Arago are clearly visible for a very large ratio of aperture size to wavelength, as is the intensity distribution.

Keywords (OCIS):

  • (050.1940) Diffraction and gratings : Diffraction
  • (140.0140) Lasers and laser optics : Lasers and laser optics

Enhancing Optical Isolator Performance in Nonreciprocal Waveguide Arrays

  • Miguel Levy, Turhan Carroll, and Ramy El-Ganainy
  • received 10/02/2014; accepted 11/18/2014; posted 11/20/2014; Doc. ID 224377
  • [full text: PDF (593) KB)]
  • Abstract: We investigate the operation of optical isolators based on magneto-optics waveguide arrays beyond the coupled mode analysis. Semi-vectorial beam propagation simulations demonstrate that evanescent tail coupling and radiation effects are responsible for degrading the device performance. Our analysis suggests that these effects can be mitigated when the array size is scaled up. In addition, we propose the use of radiation blockers in order to offset some of these effects and we show that they provide a dramatic performance improvement. Finally, we also study the robustness of the system with respect to fabrication tolerances using coupled mode theory and we show that small random variations in the system parameters tend to average out as the number of optical guiding channels increases.

Keywords (OCIS):

  • (130.2790) Integrated optics : Guided waves
  • (130.3130) Integrated optics : Integrated optics materials
  • (230.3240) Optical devices : Isolators
  • (230.7370) Optical devices : Waveguides

Tm-doped fiber CPA system with more than 200 MW peak power

  • Fabian Stutzki, Christian Gaida, Martin Gebhardt, Florian Jansen, Cesar Jauregui, Jens Limpert, and Andreas Tünnermann
  • received 10/03/2014; accepted 11/18/2014; posted 11/20/2014; Doc. ID 224431
  • [full text: PDF (1564) KB)]
  • Abstract: Tm-based fiber laser systems are an attractive approach for the development of high performance laser sources in the spectral region around 2 µm wavelength. Here we present a fiber laser system delivering a pulse peak power higher than 200 MW in combination with 24 W average power and 120 µJ pulse energy. Key components enabling this performance level are a Tm-doped large-pitch fiber with a mode field diameter of 65 µm, highly efficient dielectric gratings and a Tm-based fiber oscillator operating in the stretched-pulse regime.

Keywords (OCIS):

  • (060.2320) Fiber optics and optical communications : Fiber optics amplifiers and oscillators
  • (140.3510) Lasers and laser optics : Lasers, fiber
  • (140.7090) Lasers and laser optics : Ultrafast lasers
  • (060.5295) Fiber optics and optical communications : Photonic crystal fibers
  • (060.3510) Fiber optics and optical communications : Lasers, fiber

Photonic integrated circuit for frequency 8-tupled and 24-tupled millimeter wave signal generation

  • Ramón Maldonado-Basilio, Mehedi Hasan, Rabiaa Guemri, Frederic Lucarz, Jean-Louis de Bougrenet, and Trevor Hall
  • received 10/27/2014; accepted 11/17/2014; posted 11/19/2014; Doc. ID 225739
  • [full text: PDF (444) KB)]
  • Abstract: A photonic circuit design for implementing frequency 8-tupling and 24-tupling is proposed. The front- and back-end of the circuit comprises 4×4 MMI couplers enclosing an array of four pairs of phase modulators and 2×2 MMI couplers. The proposed design for frequency multiplication requires no optical or electrical filters, the operation is not limited to carefully adjusted modulation indexes, and the drift originated from static dc bias is mitigated by making use of the intrinsic phase relations of multi-mode interference couplers. A transfer matrix approach is used to represent the main building blocks of the design and hence to describe the operation of the frequency 8-tupling and 24-tupling. The concept is theoretically developed and demonstrated by simulations. Ideal and imperfect power imbalances in the multi-mode interference couplers, as well as ideal and imperfect phases of the electric drives to the phase modulators are analyzed.

Keywords (OCIS):

  • (250.5300) Optoelectronics : Photonic integrated circuits
  • (060.5625) Fiber optics and optical communications : Radio frequency photonics
  • (130.4110) Integrated optics : Modulators

Wavelength conversion in modulated coupled-resonator systems and their design via an equivalent linear filter representation

  • Mark Wade, Milos Popovic, and Xiaoge Zeng
  • received 09/29/2014; accepted 11/17/2014; posted 11/18/2014; Doc. ID 223918
  • [full text: PDF (578) KB)]
  • Abstract: We propose wavelength converters based on modulated coupled resonators that achieve conversion by matching the modulation frequency to the frequency splitting of the supermodes of the unmodulated system. Using temporal coupled-mode theory, we show that these time-variant systems have an equivalent linear, time-invariant filter representation that simplifies the optimal engineering of design parameters for realistic systems. Applying our model to carrier plasma-dispersion modulators as an example implementation, we calculate conversion efficiencies between -5.4 dB to -1.7 dB for intrinsic quality factors of 10^4 to 10^6. We show that the ratio of the resonance shift to the total linewidth is the most important parameter when determining conversion efficiency. Finally, we discuss how this model can be used to design devices such as frequency shifters, widely tunable radio frequency oscillators, and frequency combs.

Keywords (OCIS):

  • (130.7405) Integrated optics : Wavelength conversion devices
  • (130.3990) Integrated optics : Micro-optical devices

Concatenation of surface Plasmon resonance sensors in a single optical fiber using tilted fiber Bragg gratings

  • Mohamad Diaa Baiad and Raman Kashyap
  • received 10/03/2014; accepted 11/16/2014; posted 11/18/2014; Doc. ID 224382
  • [full text: PDF (567) KB)]
  • Abstract: An in-line multichannel surface Plasmon resonance (SPR) sensor scheme excited with tilted fiber Bragg gratings (TFBG) in a chromium and gold-coated fiber is demonstrated. The channels have different operating wavelengths, different TFBG tilt angles, and hence different refractive index operating ranges. The polarization state of each channel based on the TFBG orientation can be used to switch each SPR sensor on or off as required. This system provides an operating range from 1.40 to 1.44 RIU, and a sensitivity of around 500 nm/RIU. The multiplexing in a single optical fiber of a number of TFBG-SPR sensors is demonstrated for the first time.

Keywords (OCIS):

  • (060.2370) Fiber optics and optical communications : Fiber optics sensors
  • (240.6680) Optics at surfaces : Surface plasmons
  • (060.3735) Fiber optics and optical communications : Fiber Bragg gratings

Plasmonic Spiderweb Nanoantenna Surface for Broadband Hotspot Generation

  • Ibrahim Sendur and Rustu Tok
  • received 09/19/2014; accepted 11/16/2014; posted 11/18/2014; Doc. ID 223442
  • [full text: PDF (1341) KB)]
  • Abstract: In this study, we demonstrate a general framework for obtaining a plasmonic nanoantenna surface with a broadband polarization independent response. The plasmonic spiderweb nanoantenna surface is composed of unit cells, which form multiple resonance paths due to patterning of the metallic conductor such that electrons can find multiple ways to oscillate between the poles of the conductor. The tailoring of the conductor paths and shapes of the unit cells' patterns results in a broadband spectral response. At various resonance frequencies, the electrons oscillate along different paths between the poles of the antenna, generating broadband hot spots around those poles.

Keywords (OCIS):

  • (240.6680) Optics at surfaces : Surface plasmons
  • (250.5403) Optoelectronics : Plasmonics

Diamond photonic crystals for IR spectral range

  • Taras Kononenko, Pavel Dyachenko, and Vitaliy Konov
  • received 09/19/2014; accepted 11/16/2014; posted 11/18/2014; Doc. ID 223458
  • [full text: PDF (1321) KB)]
  • Abstract: 2D photonic crystals formed inside monocrystalline diamond to operate in IR spectral range are reported. The photonic structures consisting of 150 μm long graphitized wires arranged in square matrix with period of 4 μm were produced by laser writing with ultrashort pulses. Transmittance spectra (λ=1-14 μm) measured for the structures with increasing thickness demonstrate occurrence of few minima being different for TM and TE polarization mode. Complex refraction index of the laser-modified material was evaluated for the first time to be used in computer simulation of the structures.

Keywords (OCIS):

  • (160.4760) Materials : Optical properties
  • (220.4000) Optical design and fabrication : Microstructure fabrication
  • (230.5298) Optical devices : Photonic crystals

High-speed multispectral videography with a periscope array in a spectral shaper

  • Keisuke Goda, keiichi nakagawa, Ryoichi Horisaki, Atsushi Iwasaki, Fumihiko Kannari, ichiro sakuma, Kazuki Hashimoto, and Hikaru Mizuno
  • received 10/06/2014; accepted 11/14/2014; posted 11/18/2014; Doc. ID 224449
  • [full text: PDF (1700) KB)]
  • Abstract: We present a simple method for continuous snapshot multispectral imaging or multispectral videography that achieves high-speed spectral video recording without the need for mechanical scanning and much computation for datacube construction. The enabling component of this method is an array of periscopes placed in a prism-based spectral shaper that spectrally separates the image without image deformation. As a proof-of-principle demonstration, we show five-color multispectral video recording in the visible range (200 × 200 pixels per spectral image frame) at a record high frame rate of at least 2,800 frames per second. Our experimental results indicate that this method holds promise for various industrial and biomedical applications such as remote sensing, food inspection, and endoscopy.

Keywords (OCIS):

  • (110.0110) Imaging systems : Imaging systems
  • (120.6200) Instrumentation, measurement, and metrology : Spectrometers and spectroscopic instrumentation
  • (110.4234) Imaging systems : Multispectral and hyperspectral imaging

Low-power-penalty wavelength multicasting for 36 Gbit/s 16-QAM coherent optical signals in a silicon waveguide

  • Shiming Gao, Xiaoyan Wang, and Lingchen Huang
  • received 10/13/2014; accepted 11/14/2014; posted 11/14/2014; Doc. ID 224787
  • [full text: PDF (1190) KB)]
  • Abstract: All-optical wavelength multicasting have been experimentally demonstrated for 36 Gbit/s 16-quadrature amplitude modulation signals based on multiple four-wave mixing processes in a silicon waveguide with multiple pumps. In our experiment, dual pumps are injected together with the signal into the waveguide and nine idlers are generated, involving five wavelength multicasting channels. Coherent detection and advanced digital signal processing are employed, and the recovered constellation diagrams of the multicasting idlers show a root-mean-square error vector magnitude degradation as small as 2.74%. The bit error rate (BER) results are measured for these multicasting idlers and the power penalties are all lower than 0.96 dB at the BER of 3.8 × 10-3 (corresponding to the forward error correction threshold).

Keywords (OCIS):

  • (130.3120) Integrated optics : Integrated optics devices
  • (190.4380) Nonlinear optics : Nonlinear optics, four-wave mixing
  • (190.4390) Nonlinear optics : Nonlinear optics, integrated optics

Surface plasmon resonance in eccentric femtosecond-laser-induced fiber Bragg gratings

  • Christophe Caucheteur, Karima CHAH, Valérie Voisin, and Damien Kinet
  • received 10/16/2014; accepted 11/14/2014; posted 11/14/2014; Doc. ID 225113
  • [full text: PDF (712) KB)]
  • Abstract: Highly localized refractive index modulations are photo-written in the core of pure silica fiber using point-by-point focused UV femtosecond pulses. These specific gratings exhibit a comb-like transmitted amplitude spectrum, with polarization-dependent narrowband cladding mode resonances. In this work, eccentric gratings are surrounded by a gold sheath, allowing the excitation of surface Plasmon polaritons (SPP) with radially-polarized light. The spectral response is studied as a function of the surrounding refractive index and a maximum sensitivity of 50 nm/RIU (refractive index unit) is reported for a well-defined cladding mode resonance among the spectral comb. This novel kind of plasmonic fiber grating sensor offers rapidity of production, design flexibility and high temperature stability.

Keywords (OCIS):

  • (060.2370) Fiber optics and optical communications : Fiber optics sensors
  • (240.6680) Optics at surfaces : Surface plasmons
  • (060.3735) Fiber optics and optical communications : Fiber Bragg gratings

Bismuth-doped optical fibers and fiber lasers for a spectral region of 1600-1800 nm

  • Sergei Firstov, Sergey Alyshev, Mikhail Melkumov, Konstantin Riumkin, Alexey Shubin, and Evgeny Dianov
  • received 10/07/2014; accepted 11/13/2014; posted 11/14/2014; Doc. ID 224519
  • [full text: PDF (707) KB)]
  • Abstract: Bismuth-doped optical fibers and fiber lasers operating in 1625-1775-nm range have been developed for the first time. Now the existing bismuth-doped lasers, including the result presented in this paper, can cover O, E, S, C, L, and U telecommunication bands. Besides, new data on the nature of the bismuth-related active center were obtained and discussed.

Keywords (OCIS):

  • (060.2290) Fiber optics and optical communications : Fiber materials
  • (060.2310) Fiber optics and optical communications : Fiber optics
  • (060.2320) Fiber optics and optical communications : Fiber optics amplifiers and oscillators
  • (060.3510) Fiber optics and optical communications : Lasers, fiber

Second-harmonic generation enhancement in the presence of Tamm plasmon-polaritons

  • Andrey Fedyanin, Vladimir Bessonov, and Boris Afinogenov
  • received 09/17/2014; accepted 11/13/2014; posted 11/14/2014; Doc. ID 223240
  • [full text: PDF (358) KB)]
  • Abstract: Resonant enhancement of second-harmonic generation intensity by a factor of 50 is demonstrated in a Tamm plasmon-polariton mode excited at a metal/photonic crystal interface using nonlinear spectroscopy at various angles of incidence and polarization combinations.

Keywords (OCIS):

  • (190.4350) Nonlinear optics : Nonlinear optics at surfaces
  • (350.4238) Other areas of optics : Nanophotonics and photonic crystals
  • (250.5403) Optoelectronics : Plasmonics

SESAM Mode-Locked Red Praseodymium Laser

  • Maxim Gaponenko, Antti Harkonen, Tomi Leinonen, Mircea Guina, Thomas Sudmeyer, Guenter Huber, Christian Kraenkel, Philip Metz, and Alexander Heuer
  • received 10/09/2014; accepted 11/12/2014; posted 11/14/2014; Doc. ID 224598
  • [full text: PDF (895) KB)]
  • Abstract: We present the first semiconductor saturable absorber mirror (SESAM) mode-locked Praseodymium solid-state laser. The laser is based on a Pr3+:LiYF4 crystal as gain medium and a GaInP-quantum well-based SESAM. Self-starting continuous-wave mode-locked laser operation with an average output power of 16 mW is achieved at a center wavelength of 639.5 nm. The laser operates at a repetition rate of ~85.55 MHz and emits pulses with duration of ~18 ps.

Keywords (OCIS):

  • (140.3580) Lasers and laser optics : Lasers, solid-state
  • (140.4050) Lasers and laser optics : Mode-locked lasers
  • (140.7300) Lasers and laser optics : Visible lasers

Articles 1 to 20 of 88 Next Page >>





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