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Detection Wavelength of Strained InxGa1-xAs/gaas Very-Long-Wavelength Quantum Well Infrared Photodetectors

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Chinese Physics Letters 2007年第5期24卷 1403-1406页

作者：熊大元李宁李志锋甄红楼陆卫 National Laboratory for Infrared Physics Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083

Detection wavelength is one of the key performance indices of infrared photodetectors. We study the character of detection wavelength of the strained InxGa1-xAs/gaas very-long-wavelength （〉 12 μm） quantum well infrared photodetectors （VLW-QWIPs） characterized by the photoluminescence （PL） and photocurrent （PC） measurements. Based on the theoretical calculation and experimental data, we have built a practical model for the Inx Ga1-xAs/gaas strained VLW-QWIPs, from which the interband transitions, intersubband transition and peak detection wavelength can be determined. Afterwards, the dependences of detection wavelength and device operation mode on the In mole fraction and InxGa1-xAs well width are presented, which will be helpful for device design and optimization.

关键词： MU-M ELECTROREFLECTANCE OFFSETS gaas

Diode-Pumped Passively Q-Switched Yb：YAG Microchip Laser with a gaas as Saturable Absorber

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Chinese Physics Letters 2003年第10期20卷 1741-1743页

作者：张秋琳冯宝华张东香傅盘铭张治国赵志伟邓佩珍徐军徐晓东王勇刚马骁宇 LaboratoryofOpticalPhysics InstituteofPhysicsChineseAcademyofSciencesBeijing100080 ShanghaiInstituteofOpticsandFineMechanics ChineseAcademyofSciencesShanghai201800 InstituteofSemiconductors ChineseAcademyofSciencesBeijing100083

A passively Q-switched Yb: YAG microchip laser has been constructed by using a doped gaas as the saturable absorber as well as the output coupler. At 13.5W of pump power the device produces high-quality 3.4µJ 52ns pu... 详细信息

关键词：二极管泵浦调Q激光器 Yb：YAG微片激光器锁模激光器砷化镓可饱和吸收 gaas

Growth of high-crystallinity uniform gaas nanowire arrays by molecular beam epitaxy

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Chinese Physics B 2021年第7期30卷 578-582页

作者：亢玉彬林逢源李科学唐吉龙侯效兵王登魁方铉房丹王新伟魏志鹏 State Key Laboratory of High Power Semiconductor Lasers Changchun University of Science and TechnologyChangchun 130022China School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China

The self-catalyzed growth of Ga As nanowires(NWs)on silicon(Si)is an effective way to achieve integration between group III–V elements and Si.High-crystallinity uniform Ga As NW arrays were grown by solid-source molecular beam epitaxy(MBE).In this paper,we describe systematic experiments which indicate that the substrate treatment is crucial to the highly crystalline and uniform growth of one-dimensional nanomaterials.The influence of natural oxidation time on the crystallinity and uniformity of Ga As NW arrays was investigated and is discussed in detail.The Ga As NW crystallinity and uniformity are maximized after 20 days of natural oxidation time.This work provides a new solution for producing high-crystallinity uniform III–V nanowire arrays on wafer-scale Si substrates.The highly crystalline uniform NW arrays are expected to be useful for NW-based optical interconnects and Si platform optoelectronic devices.

关键词： gaas nanowire arrays self-catalyzed molecular beam epitaxy

An integrated power divider implemented in gaas technology

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Journal of Semiconductors 2014年第4期35卷 106-109页

作者：杜泽保杨浩张海英朱旻 Institute of Microelectronics Chinese Academy of Sciences

A compact lumped integrated power divider with low insertion loss using 0.5 μm gaas pHEMT technology is presented. The proposed power divider uses the π-type LC network for transmission line equivalence and a thin film resistor for isolation tuning simultaneously. The quality factor of the inductor is analyzed and synthesized for insertion-loss influence. The measured insertion loss is less than 0.5 dB when the operating frequency is within the range of 5.15-6.15 GHz. The return loss and isolation are better than 15 dB and 20 dB, respectively. The compact dimension of the power divider is as small as 0.9 × 0.85 mm^2. The measured results agree well with the simulated ones.

关键词： power divider gaas IPD

Photoluminescence Analysis of Injection-Enhanced Annealing of Electron Irradiation-Induced Defects in gaas Middle Cells for Triple-Junction Solar Cells

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Chinese Physics Letters 2016年第5期33卷 67-70页

作者：郑勇易天成肖鹏飞唐娟王荣 Key Laboratory of Beam Technology and Materials Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal University Beijing Radiation Center

Photolumineseenee measurements are carried out to investigate the injection-enhanced annealing behavior of electron radiation-induced defects in a gaas middle cell for GaInP/gaas/Ge triple-junction solar cells which are irradiated by 1.8 MeV with a fluence of i ~ 1015 cm-2. Minority-carrier injection under forward bias is observed to enhance the defect annealing in the gaas middle cell, and the removal rate of the defect is determined with photoluminescenee radiative efficiency recovery. Furthermore, the injection-enhanced defect removal rates obey a simple Arrhenius law. Therefore, the annealing activation energy is acquired and is equal to 0.58eV. Finally, in comparison of the annealing activation energies, the E5 defect is identified as a primary non-radiative recombination center.

关键词： gaas on cell of Photoluminescence Analysis of Injection-Enhanced Annealing of Electron Irradiation-Induced Defects in gaas Middle Cells for Triple-Junction Solar Cells in for is

Flow instability of buoyant-Marangoni convection in the LEC gaas melt

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Science China(Technological Sciences) 2008年第4期51卷 397-406页

作者： CHEN ShuXian1 & LI MingWei2,3 1 Aviation Engineering Institute, Civil Aviation Flight University of China, Guanghan 618307, China 2 Institute of Power Engineering of Chongqing University, Chongqing 400030, China 3 Research Center of Biological Function Information and Instruments of Chongqing University by Sec-ond-Term National 985 Project, Chongqing University, Chongqing 400030, China Aviation Engineering Institute Civil Aviation Flight University of China Guanghan China Institute of Power Engineering of Chongqing University Chongqing China Research Center of Biological Function Information and Instruments of Chongqing University by Second-Term National 985 Project Chongqing University Chongqing China

Flow transitions and instabilities have significant effects on the quality of the crystals. The flow and heat transfer in the LEC gaas melt are numerically studied by a time-dependent and three-dimensional turbulent flow model. The effects of the change of the buoyancy and Marangoni force on the flow state are analyzed by changing the temperature difference between the crystal and the crucible walls. The results show that the flow will transform from axisymmetric steady flow to non-axisymmetric oscillatory flow when the temperature difference exceeds the critical value, and that the mechanism of the transition is attributed to the Marangoni instability. The critical temperature differences for the flow transitions corresponding to different melt depth H are numerically predicted. Several important characteristics of the non-axisymmetric buoyant-Marangoni convection are numerically observed and compared with that of the non-axisymmetric mixed convection coupled with crystal rotation.

关键词： flow transition flow instability buoyant-Marangoni convection mixed convection LEC gaas melt

Contactless Monitoring of the Diameter-Dependent Conductivity of gaas Nanowires

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Nano Research 2010年第10期3卷 706-713页

作者： Fauzia Jabeen Silvia Rubini Faustino Martelli Alfonso Franciosi Andrei Kolmakov Luca Gregoratti Matteo Amati Alexei Barinov Andrea Goldoni Maya Kiskinova Sincrotrone Trieste S.C.P.A. Elettra LaboratoryArea Science ParkS.S.14Km.163.5I-34149 TriesteItaly Laboratorio TASC IOM-CNR Area Science ParkS.S.14Km.163.5I-34149 TriesteItaly Department of Physics Southern Illinois University Carbondale1245 Lincoln Dr.Neckers 478CarbondaleIL 62901-4401USA

Contactless monitoring with photoelectron microspectroscopy of the surface potential along individual nano-structures,created by the X-ray nanoprobe,opens exciting possibilities to examine quantitatively size-and surface-chemistry-effects on the electrical transport of semiconductor nanowires(NWs).Implementing this novel approach-which combines surface chemical microanalysis with conductivity measurements-we explored the dependence of the electrical properties of undoped gaas NWs on the NW width,temperature and surface chemistry.By following the evolution of the Ga 3d and As 3d core level spectra,we measured the position-dependent surface potential along the gaas NWs as a function of NW diameter,decreasing from 120 to~20 nm,and correlated the observed decrease of the conductivity with the monotonic reduction in the NW diameter from 120 to~20 nm.Exposure of the gaas NWs to oxygen ambient leads to a decrease in their conductivity by up to a factor of 10,attributed to the significant decrease in the carrier density associated with the formation of an oxide shell.

关键词： Semiconductor nanowires charge transport surface oxidation photoelectron X-ray microscopy charging gaas

Simultaneous Effects of External Electric Field and Conduction Band Nonparabolicity on Optical Properties of a gaas Quantum Dot Embedded at the Center of a GaAlAs Nano-Wire

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Communications in Theoretical Physics 2014年第6期61卷 765-772页

作者： Gh.Safarpour M.A.Izadi M.Novzari E.Niknam M.M.Golshan Zarghan Branch Islamic Azad University Young Researchers and Elite Club Zarghan Branch Islamic Azad University Department of Physics College of Sciences Shiraz University

An investigation of the optical properties of a gaas spherical quantum dot which is located at the center of a Ga1-xAlxAs cylindrical nano-wire has been performed in the presence of an external electric field. The band nonparabolicity effect is also considered using the energy dependent effective mass approximation. The energy eigenvalues and corresponding wave functions are calculated by finite difference approximation and the reliability of calculated wave functions is checked by computing orthogonality. Using computed energy eigenvalues and wave functions, the linear,third-order nonlinear and total optical absorption coefficients and refractive index changes are examined in detail. It is found that(i) Presence of electric field causes both blue and red shifts in absorption spectrum;(ii) The absorption coefficients shift toward lower energies by taking into account the conduction band nonparabolicity;(iii) For large values of electric field the effect of conduction band nonparabolicity is less dominant and parabolic band is estimated correctly;(iv) In the presence of electric field and conduction band nonparabolicity the nonlinear term of absorption coefficient rapidly increases by increasing incident optical intensity. In other words, the saturation in optical spectrum occurs at lower incident optical intensities.

关键词： gaas 纳米线量子点抛物线电场导带光学性质三阶非线性光学

Enhanced Fabry-Perot resonance in gaas nanowires through local field enhancement and surface passivation

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Nano Research 2014年第8期7卷 1146-1153页

作者： Shermin Arab Department of Electrical Engineering University of Southern California Los Angeles CA 90089 USA Department of Physics University of Southern California Los Angeles CA 90089 USA Department of Chemical Engineering and Materials Science University of Southern California Los Angeles CA 90089 USA Center for Energy Nanoscience University of Southern California Los Angeles CA 90089 USA

我们在光致发光(PL ) 报导实质的改进效率和 Fabry-Perot (FP ) 通过表面钝化和本地地改进的单个 gaas nanowires 的回声，甚至在房间温度要遵守的创新 FP 山峰。为赤裸的 gaas nanowires，强壮的 FP 回声山峰能在 4 K，然而并非在房间... 详细信息

我们在光致发光(PL ) 报导实质的改进效率和 Fabry-Perot (FP ) 通过表面钝化和本地地改进的单个 gaas nanowires 的回声，甚至在房间温度要遵守的创新 FP 山峰。为赤裸的 gaas nanowires，强壮的 FP 回声山峰能在 4 K，然而并非在房间温度被观察。然而，在金底层上扔 nanowires 在 PL 紧张(5X ) 导致实质的改进，到 FP 的无限的改进的 3.7X 达到顶点。有限差别的时间域(FDTD ) 模拟证明金底层通过提高的吸收(11X ) 而非提高的排放(1.3X ) 主要提高 PL 系列，预言当非放射的再结合不在时的 14X 的全部的 PL 改进。尽管有 FP 山峰的增加的紧张，更低的 Q 因素由于与内在的金底层联系的损失被观察。作为在这些 nanowires 减少非放射的再结合的一个工具，在 nanowires 的表面状态能被离子的液体( 1-ethyl-3-methylimidazolium 二度( trifluoromethylsulfonyl ) imide ( EMIM TFSI ))或 Algaas 表面层使钝化没有金底层，在房间温度完成光致发光紧张和 FP 山峰的观察的改进直到 12X 。

关键词：表面钝化纳米线 gaas 共振发光强度有限差分时域光致发光辐射复合