中国科学院机构知识库网格系统: 检索

simulation of ingan/gan light-emitting diodes with patterned sapphire substrate 会议论文 OAI收割
12th International Conference on Numerical Simulation of Optoelectronic Devices, NUSOD 2012, Shanghai, China, August 28, 2012 - August 31, 2012
Sheng Yang; Xia Chang Sheng; Simon Li Z.M.; Cheng Li Wen

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收藏 | 浏览/下载：10/0 | 提交时间：2013/09/22

Computer simulation Efficiency Extraction Finite difference time domain method Gallium nitride Optoelectronic devices Sapphire Semiconductor quantum wells Three dimensional computer graphics Time domain analysis

Observation of photogalvanic current for interband absorption in InN films at room temperature 会议论文 OAI收割
2nd ieee international nanoelectronics conference, shanghai, peoples r china, mar 24-27, 2008
Tang, CG; Chen, YH; Liu, Y; Zhang, RQ; Liu, XL; Wang, ZG; Zhang, R; Zhang, Z

收藏 | 浏览/下载：38/0 | 提交时间：2010/03/09

QUANTUM-WELLS SPIN

The spectral feature analysis of semiconductor thin disk laser (EI CONFERENCE) 会议论文 OAI收割
Optoelectronic Materials and Devices II, November 2, 2007 - November 5, 2007, Wuhan, China
作者: Li J.; Wang L.-J.; Wang L.-J.; Ning Y.-Q.; Li J.

收藏 | 浏览/下载：18/0 | 提交时间：2013/03/25

The semiconductor thin disk laser is a new type of semiconductor laser. This work gives the basic operation function of semiconductor disk laser and analyses the heat effect by the experimentally measured photoluminescence spectrum of the laser chip at different pump power and different temperature. We can see that: with increasing pump power the thermal effects of the gain material becomes seriously and causes the saturation of carrier lifetime so the electron-hole pair created in the absorbtion layer have no enough time to rate to one of the wells and the non-radiative recombination happens in the barrier. When the thermal effects becomes stronger the chip will not lasing. This phenomenon is from the smaller energy offset between barrier and quantum well. We optimize the original structure design and experimental technology. A non-absorbing AlGaAs layer who is transparent to the pumping and laser wavelength is added to confine the carriers in the quantum wells. At the same time a DBR with double reflecting band is induced to improve the absorbing efficiency of the pumping light. The single QW is replaced by the three narrow QWs This three QWs structure can add the quantum state of QW increase the recombination probability of carriers in the QWs and reduce the heat effect. The chemical etch equipment is also improved to control the surface unevenness to be within 50 nm.

High power VCSEL device with periodic gain active region (EI CONFERENCE) 会议论文 OAI收割
Optoelectronic Materials and Devices II, November 2, 2007 - November 5, 2007, Wuhan, China
作者: Zhang Y.; Liu Y.; Liu Y.; Liu Y.; Qin L.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

High power vertical cavity surface emitting lasers with large aperture have been fabricated through improving passivation lateral oxidation and heat dissipation techniques. Different from conventional three quantum well structure a periodic gain active region with nine quantum wells was incorporated into the VCSEL structure with which high efficiency and high power operation were expected. The nine quantum wells were divided into three groups with each of them located at the antinodes of the cavity to enhance the coupling between the optical field and the gain region. Large aperture and bottom-emitting configuration was used to improve the beam quality and the heat dissipation. A maximum output power of 1.4W was demonstrated at CW operation for a 400m-diameter device. The lasing wavelength shifted to 995.5nm with a FWHM of 2nm at a current of 4.8A due to the internal heating and the absence of active water cooling. A ring-shape farfield pattern was induced by the non-homogeneous lateral current distribution in large diameter device. The light intensity at the center of the ring increased with increasing current. A symmetric round light spot at the center and single transverse mode operation with a divergence angle of 16 were observed with current beyond 4.8A.

Vertical-cavity surface-emitting lasers with periodic gain structure (EI CONFERENCE) 会议论文 OAI收割
作者: Wang L.; Wang L.; Wang L.; Qin L.; Sun Y.

收藏 | 浏览/下载：14/0 | 提交时间：2013/03/25

The periodic gain structure is used as the active region of vertical-cavity surface-emitting lasers which can enhance the effective coupling between gain regions and internal optical field. The high device performance is achieved. The maximum continuous-wave output power of large aperture device with active diameter up to 400 m is as high as 1.41 W at room temperature. The low threshold current is only 0.5 A which is lower than that of the conventional device with three quantum wells. 2006 Elsevier B.V. All rights reserved.

Nonradiative recombination effect on photoluminescence decay dynamics in GaInNAs/GaAs quantum wells - art. no. 61180Z 会议论文 OAI收割
conference on ultrafast phenomena in semiconductors and nanostructure materials x, san jose, ca, jan 23-25, 2006
Sun, Z (Sun, Z.); Xu, ZY (Xu, Z. Y.); Yang, XD (Yang, X. D.); Sun, BQ (Sun, B. Q.); Ji, Y (Ji, Y.); Zhang, SY (Zhang, S. Y.); Ni, HQ (Ni, H. Q.); Niu, ZC (Niu, Z. C.)

收藏 | 浏览/下载：182/36 | 提交时间：2010/03/29

GaInNAs/GaAs quantum wells optical properties nonradiative recombination effect time-resolved photoluminescence PL decay dynamics PL thermal quenching MOLECULAR-BEAM EPITAXY GAASN ALLOYS EXCITATION

Vertical-external-cavity surface-emitting lasers operating at different wavelength: Design, numerical simulation, and characteristics (EI CONFERENCE) 会议论文 OAI收割
Optoelectronic Materials and Devices for Optical Communications, November 7, 2005 - November 10, 2005, Shanghai, China
作者: Qin L.; Jiang H.; Wang L.; Wang L.; Wang L.

收藏 | 浏览/下载：12/0 | 提交时间：2013/03/25

We describe design numerical simulation and characteristics of high-power optical pumped VECSELs at different wavelength (980nm and 1300nm). The device design realizes the integrating diode-pumped lasers with vertical-cavity surface-emitting laser structure drawing on the advantages of both. With periodical gain element structure optical pumped VECSEL is scalable to watt level output. The characteristics such as threshold condition and output power are calculated theoretically. An optimum number of quantum wells and external mirror reflectivity are obtained from the calculation results and the thermal characteristic is also considered. Finally the calculation results also predict high output power in this kind of device structure.

Theoretical analysis of 980nm high power Vertical External-cavity Surface-emitting Semiconductor Laser (VECSEL) (EI CONFERENCE) 会议论文 OAI收割
ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China
作者: Wang L.-J.; Wang L.-J.

收藏 | 浏览/下载：15/0 | 提交时间：2013/03/25

By using bottom-emitting structure we will develop laser diode (LD) pumped 980 nm VECSEL with active region of InGaAs/GaAsP/AlGaAs system. Because the thickness of barrier layer and absorption layer exceed that of quantum well single well approximation model (KP method) can be used to calculate the band structure of VECSEL. The Schrodinger equation of finite deep potential well can be adopted to calculate the energy level structures of electron heavy and light holes. According to the transition selection rule we theoretically obtained the emitting wavelength of VECSEL and calculated quasi-Femi energy of valence band and conduction band based on the analysis of energy level structure of electron and holes. By analyzing the gain of strained quantum wells we calculated the gain of VECSEL using transition matrix elements of electron heavy and light holes. We give out the threshold gain output power and other characteristic parameters. We will study the configuration of VECSEL and pumping scheme. We designed external cavity mirror active region and bottom-emitting structure. A LD-pumped vertical external cavity surface-emitting laser whose output power is greater than 1.0 W can be predicted.

Investigation of GaAs/AlGaAs interfaces by reflectance-difference spectroscopy 会议论文 OAI收割
10th international conference on defects - recognition, imaging and physics in semiconductors (drip 10), batz sur mer, france, sep 29-oct 02, 2003
作者: Ye XL; Xu B

收藏 | 浏览/下载：11/0 | 提交时间：2010/10/29

SHORT-PERIOD SUPERLATTICES RAMAN-SCATTERING QUANTUM-WELLS GROWTH ROUGHNESS SEGREGATION ALAS/GAAS ALAS GAAS

Structural and optical properties of GaAsSb/GaAs heterostructure quantum wells 会议论文 OAI收割
international conference on materials for advanced technologies, singapore, singapore, dec 07-12, 2003
作者: Zhang YH; Jiang DS

收藏 | 浏览/下载：11/0 | 提交时间：2010/11/15

molecular beam epitaxy quantum wells GaAsSb/GaAs GAAS LASERS GAIN