Broadband photoresponse based on a Te/CuInP2S6 ferroelectric field-effect transistor†

Abstract

Narrow bandgap two-dimensional (2D) semiconductors have garnered significant attention for their potential applications in next-generation optoelectronic devices. However, only few previous studies have manipulated electronic polarization, such as ferroelectric polarization and spin polarization, in conjunction with photodetectors. In this work, we designed Te ferroelectric field-effect transistors (Fe-FETs) that exhibit a clear counterclockwise hysteresis loop in transfer characteristic curves. The device achieves an ultrabroad band photoresponse from 637 nm to 10.6 μm and a high photoresponsivity (R) of 10.2 A W⁻¹ under 1 V bias. Importantly, under 637 nm laser irradiation, the device shows a very fast speed with a rise time (τ_r) of 3.86 μs and decay time (τ_d) of 6.28 μs. The proposed Te Fe-FET device provides a strategy for designing high-performance photodetectors with extensive applications.