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	Helium ion irradiation-induced microstructure evolution on the surfaces of thin nickel foils 期刊论文 OAI收割 NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS, 2018, 卷号: 428, 期号: -, 页码: 24-29 作者: Gao, J; Huang, HF; Liu, X; Ou, X; Wang, WX \| 收藏 \| 浏览/下载：17/0 \| 提交时间：2019/12/17 BEAM-INDUCED SURFACE IMPLANTATION EXFOLIATION TUNGSTEN SINGLE MODEL
	Analysis of laser jamming to satellite-based detector (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Guo L.-H.; Guo R.-H.; Wang S.-W. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 The reconnaissance satellite communication satellite and navigation satellite used in the military applications have played more and more important role in the advanced technique wars and already become the significant support and aid system for military actions. With the development of all kinds of satellites anti-satellite laser weapons emerge as the times require. The experiments and analyses of laser disturbing CCD (charge coupled detector) in near ground have been studied by many research groups but their results are not suitable to the case that using laser disturbs the satellite-based detector. Because the distance between the satellite-based detector and the ground is very large it is difficult to damage it directly. However the optical receive system of satellite detector has large optical gain so laser disturbing satellite detector is possible. In order to determine its feasibility the theoretical analyses and experimental study are carried out in the paper. Firstly the influence factors of laser disturbing satellite detector are analyzed in detail which including laser power density on the surface of the detector after long distance transmission and laser power density threshold for disturbing etc. These factors are not only induced by the satellite orbit but dependence on the following parameters: laser average power in the ground laser beam quality tracing and aiming precision and atmospheric transmission. A calculation model is developed by considering all factors which then the power density entering into the detector can be calculated. Secondly the laser disturbing experiment is performed by using LD (laser diode) with the wavelength 808 nm disturbing CCD 5 kilometer away which the disturbing threshold value is obtained as 3.5510-4mW/cm2 that coincides with other researcher's results. Finally using the theoretical model the energy density of laser on the photosensitive surface of MSTI-3 satellite detector is estimated as about 100mW/cm2 which is largely exceed the disturbing threshold and therefore verify the feasibility of using this kind of laser disturbing the satellite-based detector. According to the results. using the similar laser power density absolutely saturate the requirements to laser disturbing satellite-based detector. If considering the peak power of pulsed laser even decrease laser average power it is also possible to damage the detector. This result will provide the reliable evidences to evaluate the effect of laser disturbing satellite-based detector. 2009 SPIE.
	Optical characteristic of ion beam sputter deposited aluminum thin films (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, September 9, 2007 - September 12, 2007, Beijing, China 作者: Yang H.; Liu L.; Liu L. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 Aluminum is a typical active metal very easy to oxidize. An oxide surface layer of about 2-6nm quickly formed in air which adds difficulty to the optical constants determination. An ex-situ method is used to determine the optical constants of aluminum thin films. First Second Third alumina (Al2O3) thin film is deposited by ion beam sputter deposition. The optical constants and thickness are determined by spectral ellipsoemtry (SE). The thickness is verified by grazing x-ray reflection (GXRR) fitting method Al thin film with an Al2O3 cap layer on top is deposited. This cap layer is of the same deposition condition with the first step. By fitting the GXRR spectra based on the acquired structure information the structure information (the thickness of the aluminum and the cap layer the ellipsometric spectra are fitted. The optical constants of the aluminum layer are extracted with the aid of the Drude model. Finally surface roughness and the diffusion between Al-Al2O 3) is obtained an induced transmission filter (ITF) is designed and deposited.
	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：36/0 \| 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.