Highly sensitive phototransistors based on twodimensional GaTe nanosheets with direct bandgap  

作　　者：Pingan Hu Jia Zhang Mina Yoon Xiao-Fen Qiao Xin Zhang Wei Feng Pingheng Tan Wei Zheng Jingjing Liu Xiaona Wang Juan C. Idrobo David B. Geohegan Kai Xiao 

机构地区：[1]Key Lab of Microsystem and Microstructure, Harbin Institute of Technology, Ministry of Education, No. 2 Yikuang Street, Harbin, 150080, China [2]Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, One Bethel Valley Road, Oak Ridge, TN, 37831, USA [3]State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China

出　　处：《Nano Research》2014年第5期694-703,共10页纳米研究（英文版）

摘　　要：Highly sensitive phototransistors based on two-dimensional （2D） GaTe nanosheet have been demonstrated. The performance （photoresponsivity, detectivity） of the GaTe nanosheet phototransistor can be efficiently adjusted by using the applied gate voltage. The devices exhibit an ultrahigh photoresponsivity of 274.3 AW^-1. The detectivity of 2D GaTe devices is -10^12 Jones, which surpasses that of currently-exploited InGaAs photodetectors （10^11-10^12 Jones）. To reveal the origin of the enhanced photocurrent in GaTe nanosheets, theoretical modeling of the electronic structures was performed to show that GaTe nanosheets also have a direct bandgap structure, which contributes to the promotion of photon absorption and generation of excitons. This work shows that GaTe nanosheets are promising materials for high performance photodetectors.

关 键 词：PHOTODETECTOR gallium telluride two-dimensional semiconductor NANOSHEET 

分 类 号：TN364.3[电子电信—物理电子学] TB383[一般工业技术—材料科学与工程]