Zero‐Bias Uncooled Broadband Terahertz Detection with a TaFe_1.25Te₃/Graphene Heterostructure for Imaging and Communication

Abstract Terahertz (THz) waves offer large bandwidth with less interference and provide detailed information on materials in a non‐destructive manner, making them valuable for wireless communication, security screening, and biomedical identification. Despite the growing significance, the demand for high‐performance and ultra‐broadband THz detectors remains unmet for current limitations. In this paper, we propose a high‐sensitivity broadband THz detector utilizing the semimetal TaFe 1.25 Te 3 , leveraging its gapless electron excitation under THz illumination and fast carrier dynamics through the photothermoelectric effect at room temperature. The TaFe 1.25 Te 3 detector presents a fast response speed of 11.1/5.6 µs, a responsivity of 7.58 V W −1 , and a noise‐equivalent power (NEP) of 156 pW/Hz 1/2 at 0.1 THz. By incorporating graphene within a van der Waals heterostructure, the self‐powered response is dramatically enhanced by an order of magnitude. The TaFe 1.25 Te 3 /graphene detector features an extended response up to 0.3 THz, with an improved responsivity of 279.15 V W −1 and a lower NEP of 9 pW/Hz 1/2 at 0.1 THz, thanks to the efficient energy transfer and optimized photothermoelectric characteristics in the asymmetry architecture. Our research deepens the understanding of ultrafast hot carrier dynamics in TaFe 1.25 Te 3 and offers a promising approach to manipulate the photothermoelectric response, advancing their functionality and versatility for practical applications.