中国科学院机构知识库网格系统: 检索

Status of the PETRA IV Machine Project 会议论文 OAI收割
Thailand, 2022
作者: R. Bartolini; I.V. Agapov; A. Aloev; R. Bacher; R. Böspflug

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收藏 | 浏览/下载：10/0 | 提交时间：2023/01/05

Status of the PETRA IV project 会议论文 OAI收割
Australia, 2019
作者: I.V. Agapov; R. Bacher; M. Bieler; R. Bospflug; R. Brinkmann

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收藏 | 浏览/下载：25/0 | 提交时间：2019/08/06

The research of the accurate measure of static transfer function for the TDI CCD camera (EI CONFERENCE) 会议论文 OAI收割
3rd International Photonics and OptoElectronics Meetings, POEM 2010, November 2, 2010 - November 5, 2010, Wuhan, China
Guo-Ning L.; Long-Xu J.; Jian-Yue R.; Wen-Hua W.; Shuang-Li H.

收藏 | 浏览/下载：17/0 | 提交时间：2013/03/25

In the test course of static transfer function of TDI CCD camera because of the influence that gets environmental and artificial etc. factor the value of static transfer function measured at any time is between unceasing fluctuation so make accuracy reduce. To solve this problem a kind of accurate measurement technique of static transfer function is put forward. First before carrying out the measure of static quiet of transfer function the best test point of transfer function of the TDI CCD camera must be determined it is parallel to guarantee the rectangle target surface of parallel optical pipe and camera focal plane maintenance parallel and again guarantee target strip in rectangle target and TDI CCD in camera focal plane maintenance vertical. TDI CCD catches rectangle target image per 1000 lines of target mark image as a measures sample of static transfer function exclude because of atmosphere tremble twisted vague rectangle target mark image retain 500 distinct and steady target mark image as measure sample set. Then calculate the static transfer function of each measure sample respectively take the average of all static quiet transfer function in measure sample set as the static transfer function of camera. Finally the measure of the static transfer function for TDI CCD camera makes error analysis. Experimental results indicate that the value of the static transfer function of TDI CCD camera measured with this kind of method is 0.2923 with before measurement technique comparison the value of static transfer function has raised 0.02 makes the accuracy of the measure of static transfer function have gotten raising.

Theoretical Analysis of Emission Characteristics of Second-order Distributed Feedback Semiconductor Lasers 会议论文 OAI收割
2010
作者: Liu Y.; Liu Y.; Liu Y.; Qin L.

收藏 | 浏览/下载：11/0 | 提交时间：2013/03/28

A novel bottom-emitting vcsel's one-dimension array (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.; Wang L.; Wang L.; Liu Y.; Liu Y.

收藏 | 浏览/下载：17/0 | 提交时间：2013/03/25

A novel 980nm bottom-emitting VCSELs array with high power density and good beam property of Gaussian far-field distribution is reported. This array is composed of 5 symmetrically-arranged elements of 200m 150m and 100m-diameter with the center spacings of 300m and 250m respectively. The maximum power is 880mW at a current of 4A corresponding to lKW/cm2 average optical power density. The differential resistance is 0.09 with a threshold of 0.56A. The novel array is compared with a 300m-aperture-size single device and a 44 2-D array with 50m element aperture size and 250m centre spacing. The three devices have the same lasing area. The conclusion is that the novel array is better in the property of output power threshold current lasing spectra far-field distribution etc. 2008 SPIE.

Central hole effect on Whispering-Gallery-Mode of triangular lattice photonic crystal microcavity (EI CONFERENCE) 会议论文 OAI收割
Optoelectronic Materials and Devices III, October 27, 2008 - October 30, 2008, Hangzhou, China
作者: Zhang Y.; Wang L.; Wang L.; Wang L.; Wang Z.

收藏 | 浏览/下载：15/0 | 提交时间：2013/03/25

Whispering-Gallery-Mode (WGM) photonic crystal microcavity is a kind of photonic crystal application and can potentially be used for miniaturized photonic devices such as thresholdless lasers. In this paper we study the WGM of photonic crystal microcavities focusing on the so called H2 cavities which are formed by removing seven air holes. The WGM in these large-size cavities has some advantages compared with single defect WGM in the view of real device applications. We further add a central air hole in the cavity region to analyze the effect on WGM in the microcavity by finite difference time domain (FDTD) and plane wave expansion (PWE). It is found that the tolerance of WGM is large enough for the fabrication of electrical injection structure. 2008 SPIE.

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 - art. no. 67820O 会议论文 OAI收割
2007
作者: Sun Y.; Wang L.; Wang L.; Wang L.; Liu Y.

收藏 | 浏览/下载：7/0 | 提交时间：2013/03/28

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.

The spectral feature analysis of semiconductor thin disk laser - art. no. 67820E 会议论文 OAI收割
2007
作者: Qin L.; Li J.; Li J.; Li J.

收藏 | 浏览/下载：9/0 | 提交时间：2013/03/28