Enhancement of terahertz response in a microstructure-integrated-type-II Dirac semimetal

Abstract

Terahertz detection technology has been confronted with formidable impediments, notably the paucity of sensitivity and operating temperature for photodetectors based on traditional bulk materials. In an attempt to surmount the difficulties, we propose an innovative terahertz detector based on a PtSe2 (type-II Dirac semimetallic material) integrated asymmetric antenna structure that can enhance the terahertz photoresponse by capitalizing on meticulous fabrication procedures. Experimental outcomes demonstrate the remarkable characteristics of the photodetector in the terahertz band, encompassing fast response time (7 µs), large responsivity (3.267 A/W), and low noise equivalent power (3.96 pW/Hz0.5). These accomplishments can be ascribed to the incorporation of the asymmetric metal contact of the four-leaf clover antenna structure and the excellent thermoelectric characteristics of PtSe2. This pioneering investigation consequently unveils a novel methodology for the creation of proficient PtSe2-based terahertz detectors and serves as a catalyst for the promotion of applications and further research within the terahertz sphere.