High-Performance Infrared to Terahertz Detector Based on Topological Semimetal ZrTe3

Terahertz radiation with applications in the field of medical diagnostics, astronomical remote sensing, imaging, biomedical research, communication etc. has been widely investigated recently. As a vital part of these applications, the development of terahertz photodetectors (PDs) is urgently needed. However, the widely investigated graphene and other two-dimensional materials for terahertz PD still facing optimal combination between bandgap, dark current, and absorption capabilities. Here, adopting the zero-bandgap and high carrier density characteristics of topological semimetals (TSMs), we applied the TSM ZrTe3 for constructing high-performance terahertz PD. The PD achieved high responsivity of 0.11 A/W at 0.22 THz with response time of 4.74/4.97 ms, which exhibits great potentials for terahertz applications. Moreover, taking the zero-bandgap advantage of ZrTe3, the PD was able to respond across ultra broad spectrum range spanning from near infrared to terahertz. The responsivity of the PD was recorded from near infrared to terahertz, confirming the broad band photodetection capability.