关键词: 量子点红外探测器/
子带跃迁/
光电流谱/
分子束外延
English Abstract
Three-color InAs/GaAs quantum dot infrared photodetector with AlGaAs inserting layer
Liu Ke,Ma Wen-Quan,
Huang Jian-Liang,
Zhang Yan-Hua,
Cao Yu-Lian,
Huang Wen-Jun,
Zhao Cheng-Cheng
1.Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 61404124, 61474106, 61176014, 61307116, 61290303, 61321063), the China Postdoctoral Science Foundation (Grant No. 2015M570487), and the Aviation Science Foundation, China (Grant No. 20152436002).Received Date:31 December 2015
Accepted Date:27 January 2016
Published Online:05 May 2016
Abstract:We report on a three-color InAs/GaAs quantum dot infrared photodetector grown by molecular beam epitaxy. The InAs quantum dots with AlGaAs inserting layers are formed on an InGaAs quantum well layer as an absorber region. The detector is an nin-type device, and three photocurret peaks at 6.3, 10.2 and 11 m are observed at 77 K, respectively. Each peak is designated and the physical mechanism is discussed. The dependences of the intensities of the three peaks on the applied bias voltage are different for the positive and the negative bias conditions due to the asymmetric structure of the absorber region. The peak arising from the transition between the quantum dot ground state and a continuum state becomes weaker when the bias voltage is larger than a certain value. The physical reason is attributed to the decrease of the wavefunction overlap between the two quantum states.
Keywords: quantum dot infrared photodetector/
intersubband transition/
photocurrent spectra/
molecular beam epitaxy
