Semimetal-Interlayer-Engineered MoSe 2 /1T′-MoTe 2 /WSe 2 Heterostructure for Reconfigurable Rectification an

Abstract

Photodetectors based on two-dimensional (2D) van der Waals heterostructures have attracted considerable interest owing to their tunable electronic structures and efficient photoelectric conversion. However, simultaneously achieving low dark current, high photoresponse, and electrically reconfigurable carrier transport within a simple device architecture remains challenging. Here, we report a P-Semimetal-N (PSN) van der Waals heterostructure photodetector based on MoSe2/1T′-MoTe2/WSe2, in which the semimetallic 1T′-MoTe2 interlayer introduces multiple transport interfaces that enable flexible gate modulation while facilitating efficient photocarrier transport. Benefiting from the unique configuration, the device exhibits a rectification ratio and light-to-dark current ratio exceeding 104, together with a picoampere-level reverse dark current. It further demonstrates broadband photodetection from 220 to 1310 nm and self-powered operation at zero bias. Under 475 nm illumination, a responsivity of 2.38 A/W, a specific detectivity of 8.49 × 1011 Jones, and an external quantum efficiency of 621% are achieved at 0 V. More importantly, reversible rectification switching is realized through gate-voltage modulation, enabling continuous tuning of the rectification ratio from 10–2 to 106. Leveraging the synergy of broadband photoresponse and reconfigurable carrier transport, the device enables self-powered imaging, encoded optical communication, and optoelectronic logic operations. This work provides a viable strategy for multifunctional and programmable 2D optoelectronic systems.