Ferroelectrically tuned tunneling photodetector based on graphene/h-BN/In2Se3 heterojunction

Abstract

Transition metal dichalcogenides (TMDs) show promise for photodetection across various wavelengths. However, photoconductive devices often face various limitations such as low photoresponsivity or high dark current. This study introduces a highly sensitive photodetector using a graphene/h-BN/In2Se3 heterostructure. A substantial electron barrier (2.72 eV) at the graphene/h-BN junction effectively suppresses dark current, while the small hole barrier (1.39 eV) at the h-BN/In2Se3 junction facilitates efficient tunneling of photocarriers under illumination. The photodetector demonstrates a fast response time (Tr = 15 ms, Td = 5 ms), outstanding responsivity (1.18 × 104 μA/W), and detectivity (1.74 × 1010 Jones) at 4 V bias and 637 nm light illumination. Spectral measurements reveal a broad detection range from visible to near-infrared (450–1310 nm). Furthermore, leveraging the non-volatile ferroelectric properties of In2Se3 allows modulation of the barrier height, enabling non-volatile tunable photoconductivity. This study represents a significant advancement in ferroelectric based optoelectronic detection devices, providing strong support for applications in high-performance computing, neural networks, and related domains.