Abstract
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 ~1012 Jones, which surpasses that of currently-exploited InGaAs photodetectors (1011-1012 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. [Figure not available: see fulltext.]
| Original language | English |
|---|---|
| Pages (from-to) | 694-703 |
| Number of pages | 10 |
| Journal | Nano Research |
| Volume | 7 |
| Issue number | 5 |
| DOIs | |
| State | Published - May 2014 |
Funding
The authors gratefully acknowledge financial support from National Natural Science Foundation of China (NSFC, Nos. 61172001, 21373068, 11225421, and 10934007), and the National Basic Research Program of China (Nos. 2013CB632900 and 2009CB929301). Part of the research was conducted at the Center for Nanophase Materials Sciences, which are sponsored at Oak Ridge National Laboratory by the Scientific User Facility Division, Office of Basic Energy Sciences, U.S. Department of Energy. K. X. and M. Y. acknowledge support provided by a Laboratory Directed Research and Development award from Oak Ridge National Laboratory (ORNL). This research used resources of the National Energy Research Scientific Computing Center, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
Keywords
- gallium telluride
- nanosheet
- photodetector
- semiconductor
- two-dimensional