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Frontiers of Optoelectronics 2015年第3期8卷 329-340页

作者： Abbas GHADIMI Alireza AHADPOUR SHAL Department of Electrical Engineering Lahijan Branch islamic Azad University Lahijan Iran

In this paper, ridge waveguide quarterly wavelength shifted distributed feedback （RW-QWS- DFB） laser was modeled and analyzed. In this behavioral model, some characteristics of the device, such as thresh- old current, line width, power of output wave, spectrum of output wave, and laser stability in high powers, were investigated in accordance with different physical and geographical parameters such as sizes and structures of the layers. Considering a new proposed algorithm, the analysis of the mentioned structures was performed using transfer matrix method （TMM）, the solution of coupled waves and carrier rate equations. The results showed the advantages of some parameters in this structure.

关键词： distributed feedback laser transfer matrixmethod (TMM) transversal and lateral mode

High frame rate multi-resonance imaging refractometry with distributed feedback dye laser sensor

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Light(Science & Applications) 2015年第1期4卷 410-414页

作者： Christoph Vannahme Martin Dufva Anders Kristensen Technical University of Denmark Department of Micro-and NanotechnologyDTU NanotechDK-2800 Kgs.LyngbyDenmark

High frame rate and highly sensitive imaging of refractive index changes on a surface is very promising for studying the dynamics of dissolution,mixing and biological processes without the need for ***,a highly sensitive distributed feedback(DFB)dye laser sensor for high frame rate imaging refractometry without moving parts is *** dye lasers are low-cost and highly sensitive refractive index *** unique multi-wavelength DFB laser structure presented here comprises several areas with different grating *** two dimensions of space is enabled by analyzinglaser light from all areasin parallelwith an imaging *** this multi-resonance imaging refractometry method,the spatial position in one direction is identified from the horizontal,i.e.,spectral position of the multiple laser lines which is obtained from the spectrometer charged coupled device(CCD)*** orthogonal spatial position is obtained from the vertical spatial position on the spectrometer CCD array as in established spatially resolved ***,the imaging technique is demonstrated by monitoring the motion of small sucrose molecules upon dissolution of solid sucrose in *** omission of moving parts improves the robustness of the imaging system and allows a very high frame rate of up to 12 Hz.

关键词： distributed feedback laser label-free imaging laser sensor refractive index sensor

Directly modulated active distributed reflector distributed feedback lasers over wide temperature range operation(-40 to 85℃)

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Chinese Optics Letters 2020年第6期18卷 45-49页

作者： Gonghai Liu Gongyuan Zhao Gong Zhang Qiaoyin Lu Weihua Guo Wuhan National Laboratory for Optoelectronics&School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

We experimentally demonstrated that the distributed feedback(DFB) lasers with the active distributed reflector achieved a 25.8 Gb/s operation over a wide temperature range of -40 to 85℃. The DFB lasers can achieve additional feedback from an active distributed reflector with accurately controlled phase, and single-mode yields are not related to the position of cleave. The threshold currents of the fabricated laser are 6 mA and 20 mA at -40℃ and 85℃, respectively. The side mode suppression ratio of the fabricated laser is above 50 dB at all temperatures. Transmissions of 25.8 Gb/s after 10 km single-mode fibers with clear eye openings and less than 0.8 dB power penalty over a wide temperature range have been demonstrated as well.

关键词： distributed feedback laser wide temperature range active distributed reflector directly modulated laser

Influence of laser linewidth on performance of Brillouin optical time domain reflectometry

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Chinese Physics B 2013年第7期22卷 257-261页

作者：郝蕴琦叶青潘政清蔡海文瞿荣辉 Shanghai Key Laboratory of All Solid-state laser and Applied Techniques Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences Department of Technology Physics Zhengzhou University of Light Industry

The effects of optical sources with different laser linewidths on Brillouin optical time domain reflectometry （BOTDR） are investigated numerically and experimentally. Simulation results show that the spectral linewidth of spontaneous Brillouin scattering remains almost constant when the laser linewidth is less than 1 MHz at the same pulse width; otherwise, it increases sharply. A comparison between a fiber laser （FL） with 4-kHz linewidth at 3 dB and a distributed feedback （DFB） laser with 3-MHz linewidth is made experimentally. When a constant laser power is launched into the sensing fiber, the fitting linewidths of the beat signals （backscattered Brillouin light and local oscillator （LO）） is about 5 MHz wider for the DFB laser than for the FL and the intensity of the beat signal is about a half. Furthermore, the frequency fluctuation in the long sensing fiber is lower for the FL source, yielding about 2 MHz less than that of the DFB laser, indicating higher temperature/strain resolution. The experimental results are in good agreement with the numerical simulations.

关键词： Brillouin optical time domain reflectometry (BOTDR) laser linewidth distributed feedback laser fiber laser

Application of sampled grating to control the lasing wavelength in complex-coupled DFB laser

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Chinese Physics B 2009年第7期18卷 2868-2872页

作者：王桓朱洪亮贾凌慧陈向飞孔端花王列松张伟赵玲娟王圩 Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of Sciences Microwave-Photonics Technology Laboratory Nanjing National Laboratory of MicrostructuresNanjing University

This paper reports that the complex-coupled distributed feedback laser with the sampled grating has been designed and *** ＋1st order reflection of the sampled grating is utilized for laser single mode operation,which is 1.5387 μm in the *** typical threshold current of the device is 30 mA,and the optical output power is about 10 mW at the injection current of 100 mA.

关键词： sampled grating complex-coupled +1st order mode distributed feedback laser

Selected area growth integrated wavelength converter based on PD-EAM optical logic gate

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Journal of Semiconductors 2014年第9期35卷 92-96页

作者：牛斌邱吉芳周代兵张灿梁松陆丹赵玲娟伍剑王圩 Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

A selected area growth wavelength converter based on a PD-EAM optical logic gate for WDM application is presented, integrating an EML transmitter and a SOA-PD receiver. The design, fabrication, and DC characters were analyzed. A 2 Gb/s NRZ signal based on the C-band wavelength converted to 1555 nm with the highest extinction ratio of 7 dB was achieved and wavelength converted eye diagrams with eyes opened were presented.

关键词： distributed feedback laser electro absorption modulator (EAM) photo detector (PD) optical logicgate selected area growth (SAG) semiconductor optical amplifier (SOA)

Single mode rate equations for two sections self—pulsating DFB laser

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Chinese Physics B 2003年第5期12卷 528-531页

作者： WangChun-Lin WuJian LinJin-Tong OpticalCommunicationCentre BeijingUniversityofPostsandTelecommunicationBeijing100876China

We propose a set of single mode rate equations for multi-section distributed feedback (DFB) lasers. On the basis of the rate equations, the self-pulsation in the two-section DFB lasers with asymmetrical injection current was *** was found that the dynamic distribution of the power in two sections play key role in the self-pulsation running.

关键词： distributed feedback laser self-pulsations single mode rate equations

Optical microwave generation using two parallel DFB lasers integrated with Y-branch waveguide coupler

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Chinese Physics B 2007年第5期16卷 1459-1463页

作者：谢红云王路赵玲娟朱洪亮王圩 College of Electronic Information and Control Engineering Beijing University of Technology Beijing 100022 China National Research Center of Optoelectronic Technology Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

A new device of two parallel distributed feedback （DFB） lasers integrated monolithically with Y-branch waveguide coupler was fabricated by means of quantum well intermixing. Optical microwave signal was generated in the Y-branch waveguide coupler through frequency beating of the two laser modes coming from two DFB laser in parallel, which had a small difference in frequency. Continuous rapid tuning of optical microwave signal from 13 to 42 GHz were realized by adjusting independently the driving currents injected into the two DFB lasers.

关键词： optical microwave generation distributed feedback laser Y-branch beat-frequency

An Improved Design for an All-Optical Flip-Flop Based on a Nonlinear 3-Sections DFB laser Cavity

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Optics and Photonics Journal 2016年第5期6卷 87-100页

作者： Hossam Zoweil City of Scientific Research and Technology Applications Advanced Technology and New Materials Research Institute Alexandria Egypt

A new all optical flip-flop based on a 3-sections nonlinear semiconductor DFB laser structure is proposed and simulated. The operation of the device does not require a holding beam. Electrical current injection into an active layer provides optical gain to the laser mode. The wave-guiding layer consists of a linear grating section centered between 2 detuned nonlinear grating sections. The average refractive index in the nonlinear sections is slightly higher than the refractive index of the middle section. A negative nonlinear refractive index coefficient exists along the nonlinear sections. In the “OFF” state, the DFB structure does not provide enough optical feedback to lase due to the detuned sections. At high light intensity in structure, “ON” state, detuning decreases and the DFB structure allows for a laser mode that sustains the decrease in detuning to exist. The nonlinearity is provided by direct photon absorption at the Urbach tail. Numerical simulations using GPGPU computing show nanoseconds transition times between “OFF” and “ON” states.

关键词： All-Optical Flip-Flop distributed feedback laser Nonlinearity Switching