Sensitive and Anisotropic Room‐Temperature Terahertz Photodetection in Quasi‐1D Nodal‐Line Semimetal NbNiTe ₅

Abstract Low‐dimensional topological materials merge the benefits of reduced dimensionality with the nontrivial topological phases, garnering significant attention as promising candidates for next‐generation optoelectronic devices. The quasi‐1D nodal‐line semimetal NbNiTe ₅ showcases distinct in‐plane anisotropy alongside robust Dirac nodal‐line points, rendering it a fascinating platform for exploring the intricate interplay between novel quantum states of matter and low‐energy radiation. Here, sensitive and anisotropic terahertz photodetection driven by Dirac fermions and the intrinsic anisotropic properties of NbNiTe ₅ are presented. Leveraging the enhanced carrier transport characteristics derived from nontrivial band topology, room‐temperature responsivity of 1.36 A W ⁻¹ , noise equivalent power of 5.31 × 10 ⁻¹¹ W Hz ^−1/2 as well as fast photoresponse speed of 4.5 µs are achieved. The exceptionally high anisotropic photoresponse ratio of 84 highlights the potential for improving the performance of polarization‐sensitive photodetectors. This work is crucial for advancing the understanding of nontrivial topology and the development of terahertz photodetector technologies.