High-temperature photon-type ultra-broadband detectors based on ratchet structure

Abstract

Achieving a photodetector with high bandwidth, high sensitivity, high speed, and high operating temperature is a common goal for researchers, especially for infrared and terahertz regions due to its important application in various fields like military defense and biochemical analysis. Among photon-type terahertz (THz) detectors, heterojunction interfacial work function internal photoemission (HEIWIP) detectors demonstrate high bandwidth, high sensitivity, and high speed, but are limited by the low operating temperature. In this work, we developed an effective strategy for raising its operating temperature by introducing ratchet structures. By comparing with traditional HEIWIP, the ratchet HEIWIP exhibits a low dark current and high detectivity while retaining the ultra-broad response bandwidth. The operating temperature has been raised from 7 to 20 K in the terahertz region, which is meaningful progress in THz photon-type detection. The universality of this scheme makes it possible to be further migrated to general photon-type semiconductor detectors.