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Title: Mid-Infrared Spectrometer Based on Tunable Photoresponses in Pdse 2
Mid-infrared (mid-IR) photodetection is important for various applications, including biomedical diagnostics, security, chemical identification, and free-spacing optical communications. However, conventional “photon” mid-IR photodetectors require liquid nitrogen cooling (i.e., MCT). Furthermore, acquiring mid-IR spectra usually involves a complex and expensive Fourier Transform Infrared spectrometer, a tabletop instrument consisting of a meter-long interferometer and MCT detectors, which is not suitable for mobile and compact device applications. In this work, we present tunable photoresponsivity in the mid-IR wavelength in palladium diselenide (PdSe2) – molybdenum disulfide (MoS2) heterostructure field-effect transistors (FETs), operating at room temperature. Furthermore, we applied a tunable membrane cavity to modulate the Fabry–Pérot resonance to modulate the absorption spectrum of the device layer. We used a robust polyetherimide (PEI) membrane with CVD-grown graphene to electrically tune the membrane structure. For the next step, we will integrate the PdSe2-based photodetector and tunable membrane to increase detection sensitivity and spectrum tunability to realize the ‘learning’-based spectroscopy.  more » « less
Award ID(s):
2150561
PAR ID:
10545000
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
World Scientific Publishing Company
Date Published:
Journal Name:
International Journal of High Speed Electronics and Systems
Volume:
33
Issue:
02n03
ISSN:
0129-1564
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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