An Infrared Photoinverter With a GeSe 2-D/PbSe Heterostructure and its Application in Spectroscopy Detectors

In this letter, an infrared photoinverter with a GeSe 2-D/ $\alpha $ -PbSe heterostructure and a high detectivity ( $5.8\times 10 ^{14}$ Jones) and responsivity ( $1.26\times 10$ ⁶ V/W) has been proposed for applications in spectroscopy detectors and quick chemical gas identification. The design concept is based on three criteria: 1) an enhanced heterostructure constructed from a GeSe 2-D nanomaterial with PbSe and an abrupt PN junction; 2) a photoinverting device that can conveniently perform I-V conversion; and 3) a compatible sensing unit that includes a spectral ppb-level trace gas sensing module. Our work, which used a tunable DFB (Distributed Feedback) laser and retained high spectral sensitivity (1550-1750 nm), presents a novel technical method that meets the various requirements for cost-effective trace gas detection in the infrared region.