Based on BP/CuInP2S6 van der Waals heterojunction terahertz photodetectors with High-performance photoresponse

Abstract

The development of solid-state, integrable, and highly sensitive terahertz photodetectors plays a pivotal role in propelling the progress of terahertz technology. However, the progress of conventional semiconductor photodetectors has been hindered by factors such as material bandgap, low-temperature cooling, and optical absorption efficiency. In view of the distinctive structure and physical properties of two-dimensional (2D) materials, especially the vertical stacking without lattice mismatch and the compatibility with silicon-based optoelectronic technology, which provides a broader opportunity for nano optoelectronics. In recent years, the combination of ferroelectric localized electromagnetic field with 2D materials has opened up new avenues for designing novel optoelectronic devices, significantly augmenting detector sensitivity and expanding their wavelength response range. In this context, this paper proposes a ferroelectric field-effect transistor by integrating black phosphorus (BP) with CuInP₂S₆ (CIPS) van der Waals heterostructures and incorporating a four-leaf clover artificial microstructure to achieve high-sensitivity detection and imaging in the terahertz range. By applying gate bias to manipulate the ferroelectric polarization of the CIPS dielectric layer, the ferroelectric field-effect transistor demonstrates an exceptional voltage responsivity (374.6 V/W), extremely low noise equivalent power (0.64 nW/Hz^0.5), and a response time of 9.5 μs. The research results further expand the application range of 2D ferroelectric materials in the terahertz domain.