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	PDA modified NIR-II NaEr0.8Yb0.2F4 nanoparticles with high photothermal effect 期刊论文 OAI收割 NANOTECHNOLOGY, 2022, 卷号: 33, 期号: 38 作者: Zhan, Weifan; Zhao, Bin; Cui, Xiaoxia; Liu, Junsong; Xiao, Xusheng \| 收藏 \| 浏览/下载：40/0 \| 提交时间：2022/07/26 near-infrared-secondary rare earth nanoparticles fluorescence imaging light and heat
	Synthesis and luminescence properties of Eu3+-doped silicate nanomaterial (EI CONFERENCE) 会议论文 OAI收割 17th International Conference on Dynamical Processes in Excited States of Solids, DPC'10, June 20, 2010 - June 25, 2010, Argonne, IL, United states 作者: Zhang J.; Zhang J.; Zhang J. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In this paper we introduce a sol-gel process for preparing Y 2Si2O7: Eu3+ nanocrystals. The rare earth compounds were dispersed in the SiO2 colloids and the monodisperse nano-scale composite materials were prepared. The reactant mass fraction and heat treatment temperatures could affect the structures and emission spectrum properties of as-synthesized samples. The samples emit the strong red light upon excitation under the ultraviolet. The main peaks originate from 5D0-7F2 electric dipole transition of Eu3+. With regard to the samples treated at different temperatures the emission spectra obtained under 266 nm excitation show different shapes of spectra lines and relative intensities indicating that the Eu3+ ions have been located in different local environments. 2011 Published by Elsevier B.V.
	Vertical-external-cavity surface-emitting lasers: Numerical simulation, and characterization (EI CONFERENCE) 会议论文 OAI收割 Optoelectronic Materials and Devices III, October 27, 2008 - October 30, 2008, Hangzhou, China 作者: Qin L. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Firstly the vertical external-cavity surface-emiting lasers (VECSELs) device structure and model was given and the output characteristic was simple calculated. Then in experiment the VECSELs were grown bonded on to the heat sink and optically pumped by high-power 808nm diode laser array with fiber output module the light emission spectra were measured. Finally The thermal characteristic of the VECSELs was investigated by changing the temperature of the substrate. 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：23/0 \| 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.
	Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China Yang W.; Jingxu Z. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Large-aperture telescope can be used in surveying battlefield researching landform searching object real-time monitoring imaging detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object quantity geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology people require larger aperture in optics-electronic (OE) system. By increasing optical aperture the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors such as deadweight deformation of heat environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror precision of the system is ensured. During the designing phase one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply which was operated by the Directed Energy Directorate of the Air Force Research Laboratory Kirtland AFB NM USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.
	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：29/0 \| 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.
	Developing of in-suit long trance profiler for testing slope error of aspherical optical Elements (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China Zhou C.; Li H.; Chen C.; Zhou C.; Qian S. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 Profile error of super smooth surface of optical elements at X-ray/EUV in synchrotron radiation (SR) light beam line is described as slope error of them generally. The Long Trace Profiler (LPT) is used for testing surface slope error of SR optical elements in world generally. It is requisite to use In-suit LTP measuring surface thermal distortion of SR optical elements with high heat under high bright SR source. Authors design an In-suit LTP by means of co-path interferometer with pencil light beam. The instrument not only can be used for testing slope error of mirrors in Lab. also in situation test the distortion of mirror with high heat load at synchrotron light beam line. The device can be used to test various absolute surface figures of optical elements such as aspherieal spherical and plane. It is needless standard reference surface. It is named by LTP-III. This paper describes its basic operating principle optical system mechanical constructions DC serve motor control system array detector data acquisition system and computer system for controlling and data analysis of LTP-III. The Instrument has advantages of high accuracy low cost multifunction and wide application. Length of surface measured of optical element accuracy is 0.04 arcsec.