Photocurrent response in few-layered ReS2 devices with short and open circuits

Abstract

We perform photocurrent measurements in few-layered ReS2 with multiple electrodes using scanning photocurrent microscopy and investigate the photocurrent mechanism of the ReS2 device. In particular, we have investigated how the photocurrent responds to the different configurations of a current-collecting electrode, ground electrodes and floating electrodes. When all electrodes are electrically connected, the circuit is short. If any electrodes are floating, we refer the circuit is open. Remarkably, open-circuit devices show a similar photocurrent response with short-circuit devices. The observed photocurrent is attributed to the electron response to the modulating electric field that is generated by time-varying laser heating. We further show that the observed photocurrent is tunable by gate voltages. © 2021, The Korean Physical Society.