1 中国科学院长春光学精密机械与物理研究所， 吉林 长春 130033
2 中国科学院大学， 北京 100049
为了考察光电倍增管的性能，以使其满足空间遥感仪器在轨应用需求，利用氘灯、真空紫外单色仪、光电倍增管等构建了一套基于标准真空光电管的量子效率定标系统，依据光电倍增管的阴极量子效率测量原理，将光电倍增管改造成无电子束倍增的光电管，实现了由标准真空光电管到光电管R2078的标准传递; 并在此基础上，在国内首次实现了150～300 nm紫外-真空紫外波段光电管量子效率的直接测量。测量结果表明：由于光电管R2078的窗口材料为融石英，其在155 nm处的透过率最小，因此在155 nm处获取的量子效率最小，在230 nm波长处量子效率最大。最后对测量结果进行不确定度分析与估计，得到总的合成不确定度为3.4%。
探测器 紫外-真空紫外 定标 量子效率 光电倍增管 不确定度
Author Affiliations
Abstract
1 Institute of Optoelectronics Technology, China Jiliang University, Hangzhou 310018, China
2 School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Using the first-principles method based on the density functional theory (DFT), the work function of seven different GaN (0001) (1×1) surface models is calculated. The calculation results show that the optimal ratio of Cs to O for activation is between 3∶1 and 4∶1. Then, Cs/O activation and stability testing experiments on reflection-mode negative electron affinity GaN photocathodes are performed. The surface model [GaN (Mg): Cs] Cs-O after being activated with cesium and oxygen is used. The experiment results illustrate that the adsorption of O contained in the residual gas increases the surface potential barrier and the reduction of the effective dipole quantity is the basic cause of the quantum efficiency decay.
040.7190 Ultraviolet 160.1890 Detector materials 230.0040 Detectors 260.7210 Ultraviolet, vacuum Chinese Optics Letters
2015, 13(10): 100401
Author Affiliations
Abstract
Surface photovoltage spectroscopy equations for cathode materials with an AlxGa1 xAs buffer layer are determined in order to effectively measure the body parameters for transmission-mode (t-mode) photocathode materials before Cs-O activation. Body parameters of cathode materials are well fitted through experiments and fitting calculations for the designed AlxGa1 xAs/GaAs structure material. This investigation examines photo-excited performance and measurements of body parameters for t-mode cathode materials of different doping structures. It also helps study various doping structures and optimize structure designs in the future.
040.7190 Ultraviolet 160.1890 Detector materials 230.0040 Detectors 260.7210 Ultraviolet, vacuum Chinese Optics Letters
2012, 10(11): 110401
Author Affiliations
Abstract
1 Key Laboratory of Optoelectronic Technology and Systems of Ministry of Education of China, College of Optoelectronic Engineering, Chongqing University, Chongqing 400044, China
2 Institute of Electronic Engineering and Opto-Electric Technology, Nanjing University of Science and Technology, Nanjing 210094, China
We create a GaN photocathode based on graded AlxGa1?xN buffer layers to overcome the influence of buffer-emission layer interface on the photoemission of transmission-mode GaN photocathodes. A gate-shaped spectral response with a 260-nm starting wavelength and a 375-nm cut-off wavelength is obtained. Average quantum efficiency is 15% and short wavelength responses are almost equivalent to long wavelength ones. The fitted interface recombination velocity is 5×104 cm/s, with negligible magnitude, proving that the design of the graded buffer layers is efficient in obtaining good interface quality between the buffer and the emission layer.
紫外探测器 GaN 光电阴极 缓冲层 界面复合速率 光电发射 040.7190 Ultraviolet 160.1890 Detector materials 230.0040 Detectors 260.7210 Ultraviolet, vacuum Chinese Optics Letters
2011, 9(1): 010401
