Room-Temperature Blackbody-Sensitive Photodetector with Visible-To-Long-Wavelength-Infrared Photoresponse and Ultrafast Speed Based on a Te/PtSe2 Heterostructure

Abstract

Room-temperature blackbody-sensitive infrared photodetectors with ultra-broadband and ultrafast photoresponses are highly desired in numerous scientific and technical fields. However, it is challenging for an infrared photodetector to simultaneously possess all the aforementioned characteristics. In this study, a room-temperature Te/PtSe₂ heterostructure photodetector is established to address this challenge, utilizing the built-in field of the heterostructure, the crossing conduction and valence bands of PtSe₂, the high mobilities of both materials, and a considerable photogain. The device is photoresponsive over the ultrabroad wavelength range (519 nm–10 µm). The peak responsivity and specific detectivity reach 196.8 A W⁻¹, and 4.3 × 10⁹ cm Hz^1/2 W⁻¹, respectively, at the wavelength of 3.32 µm. The device also exhibits blackbody sensitivity, with a responsivity of 24.8 A W⁻¹, and a specific detectivity of 7.4 × 10⁸ cm Hz^1/2 W⁻¹. The photoresponse is ultrafast, corresponding to a 3 dB bandwidth of 160 kHz. The study provides new possibilities for high-performance room-temperature infrared detection.