中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
首页 机构 成果 学者
  
  1. CAS IR Grid
机构
采集方式
内容类型
发表日期
学科主题
筛选

浏览/检索结果: 共10条，第1-10条 帮助

条数/页： 排序方式：
Theoretical analysis of emission characteristics of second-order distributed feedback semiconductor lasers (EI CONFERENCE) 会议论文  OAI收割
Semiconductor Lasers and Applications IV, October 18, 2010 - October 19, 2010, Beijing, China
作者:  Liu Y.;  Liu Y.;  Qin L.;  Liu Y.;  Wang L.
收藏  |  浏览/下载：28/0  |  提交时间：2013/03/25
Based on the modified coupled-wave theory  the emission characteristics  including threshold gain  photon density distribution in the cavity  and external differential quantum efficiency for second-order DFB lasers are investigated. Numerical simulation results show that for given device structure with wavelength of 1.55 m  the feedback coupling coefficient and the surface radiation coupling coefficient of the second-order grating have great influence on the emission characteristics of the device. By choosing different duty cycles of the grating  we can change the two coupling coefficients  which affect the emission characteristics. For an overall consideration  an optimal duty cycle of 0.43 is chosen. The optimized results show that the device works without degeneracy modes and spatial burning hole. Besides  the side-mode suppress ratio (SMSR) and external differential quantum efficiency reach as high as 42 dB and 47%  respectively. 2010 SPIE.  
High power diode laser with beam coupling (EI CONFERENCE) 会议论文  OAI收割
Optoelectronic Materials and Devices III, October 27, 2008 - October 30, 2008, Hangzhou, China
作者:  Wang L.;  Liu Y.;  Wang L.;  Liu Y.;  Liu Y.
收藏  |  浏览/下载：59/0  |  提交时间：2013/03/25
As the increasing applications of the semiconductor lasers in the laser processing  the single 2-D stack optic-power density has not satisfied the actual requirements. It demands to couple several diode laser stack beams to one to improve the brightness  and it becomes the central issue to adopt the appropriate beam coupling technology which would offer high quality and high efficiency. In this paper  it mainly introduces the beam shaping and the technology of spatial coupling  polarization coupling  and wavelength coupling. The coupling key elements are presented and indicated. Finally  the development of the diode laser on beam coupling in our country fell behind through analyzing the statement of the world. Our lab is studying on polarization coupling and wavelength coupling. We gain some results by phase  which the polarization coupling efficiency can achieve 90% for two LD stacks with seven bars whose luminous wavelength is 975nm and980nm.By two 808nm diode laser coupling  the efficiency of 60% can be achieved after focusing to the beam size of 22mm2. 2008 SPIE.  
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：31/0  |  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：19/0  |  提交时间：2013/03/25
Investigation on integrated high speed DFB light source and narrow bandwidth RCE photodetector for WDM fiber communication network application 会议论文  OAI收割
conference on advanced photonic sensors, beijing, peoples r china, nov 08-10, 2000
Wang QM; Li C; Pan Z; Luo Y
收藏  |  浏览/下载：22/0  |  提交时间：2010/10/29
Determination of wavelength dependence of the effective charge carrier density of photorefractive crystals 期刊论文  OAI收割
OPTICS COMMUNICATIONS, 1999, 卷号: 163, 期号: 4-6, 页码: 212
Dou, SX; Kim, J; Yi, S; Yi, J; Cha, S; Shin, SH; Zhu, Y; Ye, PX
收藏  |  浏览/下载：17/0  |  提交时间：2013/09/17
Wavelength dependence of the effective trap density in Rh-doped BaTiO3: a comparison between theory and experiment 期刊论文  OAI收割
OPTICS COMMUNICATIONS, 1999, 卷号: 170, 期号: 1-3, 页码: 115
Chi, MJ; Dou, SX; Zhu, Y; Ye, PX
收藏  |  浏览/下载：14/0  |  提交时间：2013/09/23
Light-induced infrared absorption spectra and properties of impurity levels in doped photorefractive BaTiO3 期刊论文  OAI收割
JOURNAL OF APPLIED PHYSICS, 1997, 卷号: 82, 期号: 11, 页码: 5295
Zhang, JS; Gao, H; Dou, SX; Zhu, Y; Ye, PX
收藏  |  浏览/下载：25/0  |  提交时间：2013/09/18
Temperature dependent photorefractive properties of a Ce-doped BaTiO3 crystal 期刊论文  OAI收割
OPTICS COMMUNICATIONS, 1996, 卷号: 131, 期号: 4-6, 页码: 322
Dou, SX; Ding, Y; Eichler, HJ; Zhu, Y; Ye, PX
收藏  |  浏览/下载：19/0  |  提交时间：2013/09/23
INTENSITY-DEPENDENT ABSORPTION AND PHOTOREFRACTIVE PROPERTIES IN CERIUM-DOPED BATIO3 CRYSTALS 期刊论文  OAI收割
JOURNAL OF APPLIED PHYSICS, 1995, 卷号: 78, 期号: 7, 页码: 4323
YANG, CX; ZHANG, YH; YI, XM; YEH, PC; ZHU, Y; HUI, MJ; WU, X
收藏  |  浏览/下载：15/0  |  提交时间：2013/09/18