The Experts below are selected from a list of 97446 Experts worldwide ranked by ideXlab platform
M. A. Mahdi - One of the best experts on this subject based on the ideXlab platform.
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Brillouin slow light: substantial optical delay in the second-order Brillouin gain spectrum
Optics Letters, 2014Co-Authors: Gabriel K. W. Gan, Y. G. Shee, K. S. Yeo, G. Amouzad Madhiraji, F. R. Mahamd Adikan, M. A. MahdiAbstract:We experimentally demonstrate optical delay in the second-order Brillouin gain spectrum by incorporating a double Brillouin-frequency shifter into the system. By coinciding the seed signal with the second-order Brillouin gain spectrum, it was found that the seed signal experienced significantly larger delay as compared to the Brillouin slow light generated from the first-order Brillouin spectrum. At a Brillouin gain of 17 dB, the delay was found to be at maximum of 60 ns. This widens the window of promising opportunities into the deployment of all optical tunable delay into the existing optical signal processing.
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Enhancement of Brillouin gain efficiency in multiwavelength L-band BEFL by utilizing bi-directional Brillouin pump amplification
Journal of the Optical Society of America B, 2010Co-Authors: Mohammed Hayder Al-mansoori, M. Z. Jamaludin, M. A. Mahdi, Norashidah Md Din, Fairuz AbdullahAbstract:Enhancement of Brillouin gain efficiency in a multiwavelength L-band Brillouin-erbium comb fiber laser is presented. In this laser architecture, bi-directional amplification of the injected Brillouin pump signal within the erbium gain medium, before entering the single-mode fiber was utilized. Owing to this bi-directional pre-amplification of the Brillouin pump power, the requirement of a long single-mode fiber to increase the Brillouin gain efficiency was overcome. The shot length of a single-mode fiber was utilized to achieve a high number of output channels with high peak power. Up to 25 output channels with a constant wavelength separation of 0.089 nm were achieved at 170 mW of 1480 nm pump power and 0.54 mW of Brillouin pump power in a 0.5 km short single-mode fiber.
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Enhanced Brillouin-Erbium Fiber Laser with Brillouin Pump Pre-amplification Technique
2008 6th National Conference on Telecommunication Technologies and 2008 2nd Malaysia Conference on Photonics, 2008Co-Authors: Mohammed Hayder Al-mansoori, M. Z. Jamaludin, M. A. Mahdi, M.k. AbdullaAbstract:We demonstrate an enhanced multiwavelength Brillouin-Erbium comb fiber-laser in which the Brillouin-pump is pre-amplified before entering the single-mode fiber. By using this simple scheme, a lower external Brillouin pump power is required to create the Brillouin gain and suppress the laser cavity modes as compared to direct injection of Brillouin pump into the single-mode fiber. The proposed technique also demonstrates that the BEFL exhibits a wide tunability and can produce up to 27-stable output channels with 10.5 GHz channels spacing.
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Brillouin/Erbium fiber laser with pre-amplified Brillouin pump using ring-cavity configuration
2007 Asia Optical Fiber Communication and Optoelectronics Conference, 2007Co-Authors: N.m. Samsuri, A.k. Zamzuri, M. A. MahdiAbstract:Brillouin/Erbium fiber laser using a ring laser configuration with a pre-amplified Brillouin pump is demonstrated. This configuration generated 7 Brillouin Stokes with 0.086 nm spacing and the first-Stokes peak power is at 5.638 dBm.
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Brillouin raman comb fiber laser with cooperative rayleigh scattering in a linear cavity
Optics Letters, 2006Co-Authors: A.k. Zamzuri, Mas Izyani Md Ali, A Ahmad, Romli Mohamad, M. A. MahdiAbstract:We demonstrate a multiple-wavelength Brillouin comb laser with cooperative Rayleigh scattering that uses Raman amplification in dispersion-compensating fiber. The laser resonator is a linear cavity formed by reflector at each end of the dispersion-compensating fiber to improve the reflectivity of the Brillouin Stokes comb. Multiple Brillouin Stokes generation has been improved in terms of optical signal-to-noise ratio and power-level fluctuation between neighboring channels. Furthermore, the linewidth of the Brillouin Stokes is uniform within the laser output bandwidth.
Sulaiman Wadi Harun - One of the best experts on this subject based on the ideXlab platform.
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MULTIWAVELENGTH Brillouin-ERBIUM FIBER LASER GENERATION WITH DOUBLE-Brillouin-FREQUENCY SPACING IN A RING CAVITY
Journal of Nonlinear Optical Physics & Materials, 2013Co-Authors: R. Parvizi, Sulaiman Wadi HarunAbstract:We propose and demonstrate the most compact and stable multiwavelength Brillouin Erbium Fibre Laser (MBEFL) by incorporating a 10-km long nonzero dispersion shifted fiber (NZ-DSF) acting as a Brillouin gain medium. This proposed configuration with only a single ring cavity is able to produce odd-order Brillouin Stokes waves appear in the backward direction with the line spacing 0.16nm (~20GHz). Brillouin pump and the even Stokes orders act as a Brillouin pump in the forward direction using a pre-amplified Brillouin power approach in a ring cavity. Up to 12 odd-order Brillouin Stokes lines are observed with the Brillouin pump power of around 8 dBm at injected 980 nm pump power of 125 mW. The anti-Stokes lines are also obtained due to four wave mixing and bidirectional operation.
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distributed feedback multimode Brillouin raman random fiber laser in the s band
Laser Physics Letters, 2013Co-Authors: Harith Ahmad, Mohd Zamani Zulkifli, M H Jemangin, Sulaiman Wadi HarunAbstract:A novel S-band multimode Brillouin–Raman random fiber laser based on distributed feedback of Rayleigh scattered light is demonstrated. It relies on a short length, 7.7 km long angle-cleaved dispersion compensating fiber in a mirror-less open cavity. Two 1425 nm laser diodes at a modest operating power amplify a Brillouin pump (BP) signal, which in turn generates a multi-wavelength laser output through the stimulated Brillouin scattering. Eleven Brillouin Stokes lines, spanning from 1515.15 to 1516.00 nm, were obtained at a Raman pump power of 361.66 mW. Out of these, five odd Brillouin Stokes lines were generated with a flat peak power of about 0 dBm.
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spacing switchable multiwavelength fiber laser based on nonlinear polarization rotation and Brillouin scattering in photonic crystal fiber
IEEE Photonics Journal, 2012Co-Authors: Nurul Shahrizan Shahabuddin, Z Yusoff, Harith Ahmad, Sulaiman Wadi HarunAbstract:A new spacing-switchable multiwavelength erbium-doped fiber laser (EDFL) is demonstrated using switchable nonlinear polarization rotation (NPR) and stimulated Brillouin scattering (SBS) effects. The laser employs a 100-m-long photonic crystal fiber in conjunction with a four-port circulator in a figure-of-eight arrangement to provide the intensity-dependent transmission effect, as well as to discriminate the even-order and odd-order Brillouin Stokes to have a double-frequency Brillouin Stokes output. Without the Brillouin pump (BP), the laser operates in an NPR mode to produce at least 22 lasing wavelengths with a side mode suppression ratio of more than 10 dB and a wavelength spacing of 0.27 nm. In the Brillouin erbium fiber laser mode, at least 30 Brillouin lines with a spacing of 0.16 nm are obtained at BP power of 3 dBm and 980-nm pump power of 120 mW.
Namkyoo Park - One of the best experts on this subject based on the ideXlab platform.
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Flat amplitude equal spacing 798-channel Rayleigh-assisted Brillouin/Raman multiwavelength comb generation in dispersion compensating fiber
IEEE Photonics Technology Letters, 2001Co-Authors: Bumki Min, Pilhan Kim, Namkyoo ParkAbstract:We demonstrate a simple method of generating evenly spaced multiwavelength Brillouin comb by employing dispersion compensating fiber both for Brillouin Stokes generation and Raman amplification. Multiwavelength output of 798 Brillouin Stokes lines with average channel power of -17 dBm has been obtained with excellent flatness. Channel spacing corresponds to the Brillouin Stokes shift in dispersion compensating fiber and is estimated to be 9.4 GHz with the heterodyne detection method. Coupled interaction of Brillouin, Raman, and Rayleigh scattering explains the unique feature of proposed structure.
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flat amplitude equal spacing 798 channel rayleigh assisted Brillouin raman multiwavelength comb generation in dispersion compensating fiber
IEEE Photonics Technology Letters, 2001Co-Authors: Bumki Min, Pilhan Kim, Namkyoo ParkAbstract:We demonstrate a simple method of generating evenly spaced multiwavelength Brillouin comb by employing dispersion compensating fiber both for Brillouin Stokes generation and Raman amplification. Multiwavelength output of 798 Brillouin Stokes lines with average channel power of -17 dBm has been obtained with excellent flatness. Channel spacing corresponds to the Brillouin Stokes shift in dispersion compensating fiber and is estimated to be 9.4 GHz with the heterodyne detection method. Coupled interaction of Brillouin, Raman, and Rayleigh scattering explains the unique feature of proposed structure.
Yahei Koyamada - One of the best experts on this subject based on the ideXlab platform.
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simulating and designing Brillouin gain spectrum in single mode fibers
Journal of Lightwave Technology, 2004Co-Authors: Yahei Koyamada, S Sato, Shinki Nakamura, Hideyuki Sotobayashi, Wataru ChujoAbstract:For many fiber applications, the Brillouin gain spectrum (BGS) contains important information including the Brillouin frequency shift, the Brillouin spontaneous linewidth, and the Brillouin gain coefficient. This paper is the first, to the best of our knowledge, to present an accurate numerical simulation of the BGS in single-mode fibers. The simulated and measured BGS were in good agreement. Through repeated numerical simulations, we revealed a tendency of the peak Brillouin gain coefficient that determines the stimulated Brillouin scattering threshold.
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development of a distributed sensing technique using Brillouin scattering
Journal of Lightwave Technology, 1995Co-Authors: Tsuneo Horiguchi, Mitsuhiro Tateda, Kaoru Shimizu, Toshio Kurashima, Yahei KoyamadaAbstract:This paper reviews the developments of a distributed strain and temperature sensing technique that uses Brillouin scattering in single-mode optical fibers. This technique is based on strain- and temperature-induced changes in the Brillouin frequency shift. Several approaches for measuring the weak Brillouin line are compared. >
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measurement of distributed strain and temperature in a branched optical fiber network by using Brillouin optical time domain reflectometry otdr
Tenth International Conference on Optical Fibre Sensors, 1994Co-Authors: Kaoru Shimizu, Tsuneo Horiguchi, Yahei KoyamadaAbstract:A new scheme is proposed for sensing distributed strain and temperature in optical fibers. This scheme uses Brillouin scattering as the sensing mechanism and a branched optical fiber network as the sensing fibers. Brillouin optical time domain reflectometry (OTDR) makes it possible to distinguish Brillouin scattered lightwaves from different optical fiber branches in the network when different Brillouin frequency shifts are assigned to each branch.
Peter T. Rakich - One of the best experts on this subject based on the ideXlab platform.
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A silicon Brillouin laser.
Science, 2018Co-Authors: Nils T. Otterstrom, Eric A. Kittlaus, Ryan O. Behunin, Zheng Wang, Peter T. RakichAbstract:Brillouin laser oscillators offer powerful and flexible dynamics as the basis for mode-locked lasers, microwave oscillators, and optical gyroscopes in a variety of optical systems. However, Brillouin interactions are markedly weak in conventional silicon photonic waveguides, stifling progress toward silicon-based Brillouin lasers. The recent advent of hybrid photonic-phononic waveguides has revealed Brillouin interactions to be one of the strongest and most tailorable nonlinearities in silicon. In this study, we have harnessed these engineered nonlinearities to demonstrate Brillouin lasing in silicon. Moreover, we show that this silicon-based Brillouin laser enters a regime of dynamics in which optical self-oscillation produces phonon linewidth narrowing. Our results provide a platform to develop a range of applications for monolithic integration within silicon photonic circuits.
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Brillouin lasers and amplifiers in silicon photonics
Integrated Optics: Devices Materials and Technologies XXII, 2018Co-Authors: Peter T. Rakich, Eric A. Kittlaus, Nils T. Otterstrom, Ryan O. BehuninAbstract:Using a new class of optomechanical waveguides that produce large Brillouin nonlinearities, we realize Brillouin lasers, Brillouin amplifiers, and Brillouin-based signal processing technologies in silicon photonics. Counterintuitively, the same nanophotonic silicon waveguides that greatly enhance both Kerr and Raman nonlinearities exhibit vanishingly small Brillouin nonlinearities. Only with the advent of new optomechanical waveguides—that guide both light and sound—have Brillouin interactions been transformed into the strongest and most tailorable nonlinearities in silicon. We summarize progress in the rapidly growing field of integrated Brillouin photonics, and explain how a variety of simulated lightscattering processes can be engineered to (1) create Brillouin-based optical amplifiers, (2) tailor optical susceptibility, and (3) create new signal processing technologies in silicon photonics. Finally, we harness Brillouin-based opticalamplification to create the first silicon-based Brillouin lasers and we discuss their performance characteristics.
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a silicon Brillouin laser
arXiv: Optics, 2017Co-Authors: Nils T. Otterstrom, Eric A. Kittlaus, Ryan O. Behunin, Zheng Wang, Peter T. RakichAbstract:Brillouin laser oscillators offer powerful and flexible dynamics as the basis for mode-locked lasers, microwave oscillators, and optical gyroscopes in a variety of optical systems. However, Brillouin interactions are exceedingly weak in conventional silicon photonic waveguides, stifling progress towards silicon-based Brillouin lasers. The recent advent of hybrid photonic-phononic waveguides has revealed Brillouin interactions to be one of the strongest and most tailorable nonlinearities in silicon. Here, we harness these engineered nonlinearities to demonstrate Brillouin lasing in silicon. Moreover, we show that this silicon-based Brillouin laser enters an intriguing regime of dynamics, in which optical self-oscillation produces phonon linewidth narrowing. Our results provide a platform to develop a range of applications for monolithic integration within silicon photonic circuits.
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Noise and dynamics in forward Brillouin interactions
Physical Review A, 2016Co-Authors: Prashanta Kharel, Ryan O. Behunin, William H. Renninger, Peter T. RakichAbstract:In this paper, we explore the spatio-temporal dynamics of spontaneous and stimulated forward Brillouin scattering. This general treatment incorporates the optomechanical coupling produced by boundary-induced radiation pressures (boundary motion) and material-induced electrostrictive forces (photo-elastic effects), permitting straightforward application to a range of emerging micro- and nano-scale optomechanical systems. Through a self-consistent fully coupled nonlinear treatment, developed within a general Hamiltonian framework, we establish the connection between the power spectral density of spontaneously scattered light in forward Brillouin interactions and the nonlinear coupling strength. We show that, in sharp contrast to backward Brillouin scattering, noise-initiated stimulated forward Brillouin scattering is forbidden in the majority of experimental systems. In fact, the single-pass gain, which characterizes the threshold for energy transfer in back-scattering processes, is negative for a large class of forward Brillouin devices. Beyond this frequent experimental case, we explore mechanisms for dispersive symmetry breaking that lead to amplification and dynamics reminiscent of backward Brillouin scattering.
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Tailorable stimulated Brillouin scattering in silicon nanophotonics
Nonlinear Frequency Generation and Conversion: Materials Devices and Applications XII, 2013Co-Authors: Peter T. Rakich, Heedeuk Shin, Wenjun Qiu, Robert L. Jarecki, Jonathan A. Cox, Roy H. Olsson, Andrew Starbuck, Zheng WangAbstract:We examine the physics of traveling-wave photon-phonon coupling within nanoscale silicon waveguides and explore a host of new Brillouin-based signal processing technologies enabled by tailorable stimulated Brillouin processes in silicon photonics. Theoretical analysis of Brillouin coupling at sub-wavelength scales is presented, revealing that strong light-boundary interactions produce large radiation pressures mediated Brillouin nonlinearities. Experimental results demonstrating stimulated Brillouin scattering in silicon waveguides for the first time are also presented, revealing 1000 times larger forward stimulated Brillouin gain coeffcients than any prior system.
