A candidate material EuSn2As2-based terahertz direct detection and imaging
Changlong Liu, Yi Liu, Zhiqingzi Chen, Shi Zhang, Chaofan Shi, Guanhai Li, Xiao Yu, Zhiwei Xu, Libo Zhang, Wenchao Zhao, Xiaoshuang Chen, Wei Lü, Lin Wang
Abstract
Abstract Exploring the photoelectric performance of emerging materials represented by graphene, black phosphorus and transition metal dichalcogenides is attracting enormous research interest for a wide range of electronic and photonic applications. The realization of low-power consuming photodetectors with high sensitivity and fast photoresponse in the terahertz band remains one of the profound challenges in optoelectronics. In this study, a material-EuSn 2 As 2 has been successfully implemented to realize highly sensitive terahertz photodetectors. The non-equilibrium dynamics in a two-dimensional plane allow an optionally switching between different styles of direct photon-conversions: the analogous photoconductive and photovoltaic modes spontaneously supported by the intrinsic electronic system. The prototype devices exhibited excellent sensitivity of 0.2–1.6 A/W (0.3–2.4 kV/W) from 0.02 to 0.30 THz at room temperature, corresponding to a noise-equivalent power <30pW/Hz 0.5 and a fast response time <16 μs. The versatile switching behaviour and performance of the EuSn 2 As 2 flakes-based terahertz detectors were validated via rigorous full-dimension and imaging experiments. These results open the feasibility avenues for low-energy photoelectronic applications of EuSn 2 As 2 material.