The Experts below are selected from a list of 255 Experts worldwide ranked by ideXlab platform
Gang Wang - One of the best experts on this subject based on the ideXlab platform.
-
A Novel Equivalent Circuit Model for Separate Absorption Grading Charge Multiplication Avalanche Photodiode (APD)-Based Optical Receiver
Journal of Lightwave Technology, 2010Co-Authors: Gang WangAbstract:A novel equivalent circuit for separate absorption grading charge multiplication (SAGCM) APDs composed of basic circuit components is developed. The model is applied to simulate the frequency performance of APDs, and the simulating results show a well-reasonable agreement with the physical model calculation and experimental data. The influence of three important factors on frequency performance, including carrier transit Time, avalanche Buildup Time, and parasitic elements (consisted of resistance, inductance, and capacitance of APDs) are investigated. Using this model, the cosimulation of the packaged APD\transimpedance amplifier (TIA)-module is also carried out. We found that the resonance of parasitic inductance and capacitance can be utilized to compensate the attenuation of high-speed APD\ TIA circuit board.
-
Equivalent Circuit Modeling of Separate Absorption Grading Charge Multiplication Avalanche Photodiode
Journal of Lightwave Technology, 2009Co-Authors: Yu Xiang Mai, Gang WangAbstract:In this paper, a novel equivalent circuit model for the frequency performance of separate absorption grading charge multiplication (SAGCM) avalanche photodiode (APD) is developed. This model includes effects of carrier transit Time, avalanche Buildup Time, and parasitic RC elements. Based on the equivalent circuit model, frequency and bandwidth characteristics of SAGCM APD can be simulated in advance to device fabrication, and the simulation results are in good agreement with experimental data. Conventional pin photodiodes can also be simulated as a special case when M=1. In addition, the frequency response of SAGCM APDs and pin photodiodes with different illumination directions are investigated.
Keyu Chen - One of the best experts on this subject based on the ideXlab platform.
-
High-Efficiency Optical Parametric Oscillator Based on Stimulated Brillouin Scattering Pulse Shaping
IEEE Photonics Journal, 2019Co-Authors: Yulei Wang, Hang Yuan, Qingzheng Wang, Chengyu Zhu, Hengkang Zhang, Keyu ChenAbstract:We present an optical parametric oscillator (OPO) that uses a pump pulse shape tailored by stimulated Brillouin scattering. The theoretical analysis is carried out for comparison between Gaussian pump and the step function pulse pump. The steep leading edge of the pulse helps minimize the Buildup Time of the OPO when applied to step function pulse. The study then focuses on obtaining step function pulse through stimulated Brillouin scattering pulse compression. With this control of the pump pulse's temporal shape, the experimental OPO energy conversion efficiency is 34.3%. Compared with an OPO pumped by a Gaussian-shaped pulse, the oscillation threshold is reduced and the energy conversion efficiency is improved by around 10%.
Ci-ling Pan - One of the best experts on this subject based on the ideXlab platform.
-
Pulse Buildup dynamics of an actively mode-locked laser diode array in the external cavity
IEEE Journal of Quantum Electronics, 1995Co-Authors: Chi-luen Wang, Jahn-chung Kuo, Chong-min Chang, Ci-ling PanAbstract:[[abstract]]Dynamic pulse evolution characteristics of an actively mode-locked laser diode array in the external cavity have been investigated, Numerical calculations based on modified traveling-wave rate equations reproduce experimentally observed pulse and spectral width evolution and show that the Buildup Time is about 45 round-trips, We have also performed a theoretical analysis to understand which of the laser operating parameters would affect the Buildup dynamics, It is shown that either higher de bias current or larger radiative recombination coefficient (which is inversely proportional to the excited-state lifeTime) will render the laser exhibiting shorter steady-state pulse width and faster evolution to the steady state, Other parameters affecting the Buildup, but to a lesser extent, include the radio-frequency (RF) modulation current, spontaneous emission coefficient, and gain coefficient, The power reflectivities of the output mirror and the antireflection coated diode facet, on the other hand, have little effect on the pulse width and Buildup Time for single pulse generation[[fileno]]2010144010062[[department]]物理
-
Buildup of steady-state picosecond pulses in an actively mode-locked laser-diode array.
Optics letters, 1991Co-Authors: Jahn-chung Kuo, C.-s. Chang, Ci-ling PanAbstract:We have studied experimentally the temporal and spectral characteristics of an actively mode-locked laserdiode array in an external cavity as it evolves to the steady state. It is found that the Buildup Time to steadystate picosecond pulses takes less than 45 round trips. The number of clusters of the longitudinal-mode spectrum reduces during the evolution and finally approaches a steady-state spectral distribution with the pulse energy mainly distributed among a few clusters near the line center.
D. Welford - One of the best experts on this subject based on the ideXlab platform.
-
Temporal criterion for single-frequency operation of passively Q-switched lasers.
Optics letters, 1999Co-Authors: Y. Isyanova, D. WelfordAbstract:An analytical expression for the difference in Buildup Time between two longitudinal modes in a passively Q -switched laser resonator is developed and compared with experimental laser data. The results support the following temporal criterion for single-frequency, passively Q -switched operation: The difference in Buildup Time between any two longitudinal modes of the laser resonator should be comparable with or greater than the laser pulse duration to ensure single-frequency operation.
J.w. Sulhoff - One of the best experts on this subject based on the ideXlab platform.
-
A 24-channel wavelength-selectable Er-fiber ring laser with intracavity waveguide-grating-router and semiconductor Fabry-Perot filter
IEEE Photonics Technology Letters, 1998Co-Authors: K.-y. Liou, Uziel Koren, C. Chen, Ellsworth Burrows, K. Dreyer, J.w. SulhoffAbstract:We present an Er-doped fiber ring laser that operates with a single wavelength, which is selectable from any channel wavelength of a 24-channel silica waveguide grating router. A semiconductor Fabry-Perot optical amplifier is used as an intracavity narrow-band filter to stabilize laser oscillation in a single axial mode. We show by experiment and a theoretical model that the long cavity mode Buildup Time of the Er-fiber laser and multiple passes through the intracavity filter can effectively stabilize the laser output in a single mode. An electroabsorption modulator is used to modulate the laser output at a selected wavelength. Error-free performance is demonstrated, we believe for the first Time, for a waveguide grating router fiber laser at 5 Gb/s.
