Controllable polarity photoresponse and imaging based on MoS₂/MLG/MoTe₂ heterostructure

The realization of controllable polarity photoresponse within a single device is a crucial advancement for simulating biological bipolar vision cells to drive the development of next-generation optoelectronic technologies. Nevertheless, current polarity photodetectors face significant challenges in fully suppressing symmetric photocurrent cancellation and optimizing carrier transport efficiency. Here, we propose a graphene-intercalated MoS₂/MoTe₂ heterojunction, featuring a tailorable built-in electric field and a high efficiency transport channel. Spatially resolved photocurrent reveals that the controllable polarity photoresponse originates from the bias-dependent equivalent built-in electric field of MoS₂/MLG/MoTe₂ heterojunction. The controllable polarity photoresponse realizes a large-area uniform “heart-shaped” photocurrent region. In enhanced polarity photoresponse mode, the photodetector exhibits broadband detection capabilities from visible (638 nm) to infrared (1550 nm) light, achieving a high responsivity of 18.1 A/W and an excellent detectivity of 2.8 × 10¹² Jones, as well as fast response times of 94/119 µs. Furthermore, precise imaging with a resolution better than 0.5 mm was successfully demonstrated, highlighting its polarity photoresponse for practical imaging applications. This work provides a new paradigm for controllable polarity photoresponse programmed by intercalated low-dimensional material structures, paving the way for next-generation intelligent sensing chips.