A van der Waals heterostructure based on nickel telluride and graphene with spontaneous high-frequency photoresponse Available to Purchase

Terahertz detectors have potential applications in various fields including security inspection, biomedicine, and noninvasive quality inspection due to their ability to detect terahertz radiation. However, traditional detection materials have reached their bottlenecks due to difficulties in the breakthrough of fundamental principles for terahertz light. In this work, a terahertz detector based on a NiTe₂–graphene van der Waals heterostructure has been developed to inhibit the dark current and thermal-agitation noise at room temperature. The hetero-integration of NiTe₂ and graphene exhibits enhanced photon-absorption ability and its downconversion into a direct current. The experimental results show that the peak photoresponsivity of our photodetector is 1.31 A W⁻¹ at 0.28 THz, and the corresponding noise equivalent power is 17.56 pW Hz^−1/2, which rivals commercially thermal-based photodetectors. Our device has already shown capabilities of large-area imaging, fast speed, and high signal-to-noise ratio, which can be rendered as an important step for exploring topological semimetal optoelectronics.