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Dual-wavelength distributed bragg reflector semiconductor laser based on a composite resonant cavity

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Chinese Physics B 2012年第9期21卷 301-304页

作者：陈琤赵玲娟邱吉芳刘扬王圩娄采云 Key Laboratory of Semiconductor Materials Science Institute of SemiconductorsChinese Academy of Sciences State Key Laboratory of Integrated Optoelectronics Department of Electronics EngineeringTsinghua University

We report a monolithic integrated dual-wavelength laser diode based on a distributed bragg reflector （DBR） composite resonant cavity. The device consists of three sections, a DBR grating section, a passive phase section, and an active gain section. The gain section facet is cleaved to work as a laser cavity mirror. The other laser mirror is the DBR grating, which also functions as a wavelength filter and can control the number of wavelengths involved in the laser action. The reflection bandwidth of the DBR grating is fabricated to have an appropriate value to make the device work at the dual-wavelength lasing state. We adopt the quantum well intermixing （QWI） technique to provide low-absorption loss grating and passive phase section in the fabrication process. By tuning the injection currents on the DBR and the gain sections, the device can generate 0.596 nm-spaced dual-wavelength lasing at room temperature.

关键词： dual-wavelength laser distributed bragg reflector quantum well intermixing

Numerical Simulation of an All Optical Flip-Flop Based on a Nonlinear distributed bragg reflector Laser Structure

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Optics and Photonics Journal 2016年第9期6卷 217-228页

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

A new design for an all optical flip flop is introduced. It is based on a nonlinear distributed bragg reflector (DBR) semiconductor laser structure. The device does not require a holding beam. An optical gain medium confined between 2 bragg reflectors forms the device. One of the bragg reflectors is detuned from the other by making its average refractive index slightly higher, and it has a negative nonlinear coefficient that is due to direct absorption at Urbach tail. At low light intensity in the structure, the detuned bragg reflector does not provide optical feedback to start a laser mode. An optical pulse injected to the structure reduces the detuning of the nonlinear bragg reflector and a laser mode builds up. The device is reset by detuning the second bragg reflector optically by an optical pulse that generates electron-hole pairs by direct absorption. A mathematical model of the device is introduced. The model is solved numerically in time domain using a general purpose graphics processing unit (GPGPU) to increase accuracy and to reduce the computation time. The switching dynamics of the device are in nanosecond time scale. The device could be used for all optical data packet switching/routing.

关键词： All-Optical Flip-Flop distributed bragg reflector Nonlinear Grating GPGPU

975 nm multimode semiconductor lasers with high-order bragg diffraction gratings

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Journal of Semiconductors 2024年第3期45卷 38-44页

作者： Zhenwu Liu Li Zhong Suping Liu Xiaoyu Ma National Engineering Research Center for Optoelectronic Devices Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Sciences and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China

The 975 nm multimode diode lasers with high-order surface bragg diffraction gratings have been simulated and calcu-lated using the 2D finite difference time domain(FDTD)algorithm and the scattering matrix method(SMM).The periods and etch depth of the grating parameters have been optimized.A board area laser diode(BA-LD)with high-order diffraction grat-ings has been designed and fabricated.At output powers up to 10.5 W,the measured spectral width of full width at half maxi-mum(FWHM)is less than 0.5 nm.The results demonstrate that the designed high-order surface gratings can effectively nar-row the spectral width of multimode semiconductor lasers at high output power.

关键词： laser diodes distributed bragg reflector high order gratings high power laser diodes narrow spectrum width

In situ growth monitoring of AlGaN/GaN distributed bragg reflectors at 530 nm using a 633 nm laser

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Journal of Semiconductors 2010年第9期31卷 53-58页

作者：文锋黄黎蓉姜波童梁柱徐巍刘德明 Wuhan National Laboratory for Optoelectronics College of Opto-Electronics Science & EngineeringHuazhong University of Science & Technology

The metal-organic chemical vapor deposition（MOCVD） growth of AlGaN/GaN distributed bragg reflectors （DBR） with a reflection peak at 530 nm was in situ monitored using 633 nm laser reflectometry.Evolutions of in situ reflected reflectivity for different kinds of AlGaN/GaN DBR were simulated by the classical transfer matrix method.Two DBR samples,which have the same parameters as the simulated structures,were grown by MOCVD.The simulated and experimental results show that it is possible to evaluate the DBR parameters from the envelope shape of the in situ reflectivity spectrum.With the help of the 633 nm laser reflectometry,a DBR light emitting diode（LED） was grown.The room temperature photoluminescence spectra show that the reflection peak of the DBR in the LED is within the design region.

关键词： light emitting diode metal-organic chemical vapor deposition GaN distributed bragg reflector

Enhanced light output power in InGaN/GaN light-emitting diodes with a high reflective current blocking layer

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Journal of Semiconductors 2012年第7期33卷 56-59页

作者：张晓洁杨瑞霞王静辉 College of Information Engineering Hebei University of Technology The 13th Research Institute China Electronics Technology Group Corporation

The light output power of an InGaN/GaN light-emitting diode is improved by using a SiO2/TiO2 distributed bragg reflector （DBR） and an A1 mirror as a hybrid reflective current blocking layer （CBL）. Such a hybrid reflective CBL not only plays the role of the CBL by enhancing current spreading but also plays the role of a reflector by preventing photons near the p electrode pad from being absorbed by a metal electrode. At a wavelength of 455 nm, a 1.5-pair of SiO2/TiO2 DBR and an A1 mirror （i.e. 1.5-pair DBR＋A1） deposited on a p-GaN layer showed a normal-incidence reflectivity as high as 97.8%. With 20 mA current injection, it was found that the output power was 25.26, 24.45, 23.58 and 22.45 mW for the LED with a 1.5-pair DBR＋AI CBL, a 3-pair DBR CBL, SiO2 CBL and without a CBL, respectively.

关键词： distributed bragg reflector Al current blocking layer light-emitting diode

Modified-DBR-based semi-omnidirectional multilayer anti-reflection coating for tandem solar cells

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Chinese Physics B 2014年第2期23卷 609-613页

作者： Ali Bahrami Shahram Mohammadnejad Nima Jouyandeh Abkenar Nanoptronics Research Center Department of Electrical and Electronics EngineeringIran University of Science and Technology

In this paper, multilayer antireflection coatings are designed by modifying the thickness of two and three paired layer distributed bragg reflector （DBR） structure. Our proposed DBR-based structures show antireflection behaviors, in spite of the reflection treatment in traditional DBR structures. Firstly, the proposed structures are designed to be equivalent to the theoretical ideal triple-layer （TL） antireflection coating （ARC）. Therefore, the problem of finding a suitable material for the middle layer of triple structure is solved. Simulation results show the significant equivalency for the reflectance of proposed structures to the ideal TL ARC at the same wavelengths and incident angles. Also, the design of the structure is changed in order to present the constant reflectance coefficient over a wide range of wavelengths. This structure enhances the omni-directionality of the multilayer ARC.

关键词： antireflection coating distributed bragg reflector solar cell

Monolithic white LED based on Al_xGa_(1-x) N/InyGa_(1-y)N DBR resonant-cavity

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Journal of Semiconductors 2009年第1期30卷 30-33页

作者：陈宇黄黎蓉朱珊珊 College of Optoelectronics Science & Engineering Huazhong University of Science and Technology Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

A monolithic white light-emitting diode （LED） with blue and yellow light active regions has been designed and studied. With the AlxGa1-xN/InyGa1-yN distributed bragg reflector （DBR） resonant-cavity, the extraction... 详细信息

关键词： monolithic white light-emitting diode distributed bragg reflector resonant-cavity

GaN-based high-voltage light-emitting diodes with backside reflector

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Journal of Semiconductors 2014年第7期35卷 97-101页

作者：黄华茂王洪黄晓升胡金勇 Engineering Research Center for Optoelectronics of Guangdong Province Department of PhysicsSchool of ScienceSouth China University of Technology

High-voltage light-emitting diodes （HV-LED） with backside reflector, including Ti305/SiO2 distributed bragg reflector （DBR） or hybrid reflector combining DBR and Al or Ag metal layer, are investigated using Monte Carlo ray tracing method. The hybrid reflector leads to more enhancement of light-extraction efficiency （LEE）. Moreover, the LEE can also be improved by redesigning the thicknesses of DBR. HV-LED with four redesigned DBR pairs （4-MDBR）, and those with a hybrid reflector combining 4-MDBR and Al metal layer （4-MDBR-Al）, are fabricated. Compared to 4-MDBR, the enhancement of light-output power induced by 4-MDBR-A1 is 4.6%, which is consistent with the simulated value of 4.9%.

关键词： high-voltage light-emitting diodes hybrid backside reflector distributed bragg reflector metal re-flector light extraction efficiency

An improved design for Al Ga N solar-blind avalanche photodiodes with enhanced avalanche ionization

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Chinese Physics B 2017年第3期26卷 588-591页

作者：汤寅蔡青杨莲红董可秀陈敦军陆海张荣郑有炓 Key Laboratory of Advanced Photonic and Electronic Materials School of Electronic Science and EngineeringNanjing University Department of Physics Changji College School of Mechanical and Electronic Engineering Chuzhou University

To enhance the avalanche ionization, we designed a new separate absorption and multiplication AlGaN solarblind avalanche photodiode （APD） by using a high/low-Al-content AlGaN heterostructure as the multiplication region instead of the conventional AlGaN homogeneous layer. The calculated results show that the designed APD with Al0.3Ga0.7N/Al0.45Ga0.55N heterostructure multiplication region exhibits a 60% higher gain than the conventional APD and a smaller avalanche breakdown voltage due to the use of the low-Al-content Al0.3Ga0.7N which has about a six times higher hole ionization coefficient than the high-Al-content Al0.45Ga0.55N. Meanwhile, the designed APD still remains a good solar-blind characteristic by introducing a quarter-wave A1GaN/A1N distributed bragg reflectors structure at the bottom of the device.

关键词： AlGaN deep ultraviolet photoelectric detector distributed bragg reflector