Work

Infrared Illumination-Induced Responsivity Enhancement in Photoelectric Tunable-Step Terahertz Detectors

Year: 2026

Type: article

Abstract: Quantum phenomena in two-dimensional electron gases (2DEGs) provide new opportunities for high-responsivity far-infrared detection. A prime example is photoelectric tunable-step (PETS) terahertz (THz) detectors, which use the in-plane photoelectric (IPPE) effect as a sensitive photonic detection mechanism. Here, we show that the terahertz sensitivity of this quantum photodetection mechanism can be dynamically tuned by using infrared illumination. We leverage the persistent photoconductivity (PPC) effect in AlGaAs/GaAs-based heterostructures to tune the device performance by adjusting the electron density and mobility of the channel. Our approach enables optimization of the responsivity for different operating modes and dynamic control over the output impedance of PETS terahertz detectors of approximately one order of magnitude. We provide an explanation for the underlying physics that advances the understanding of quantum photodetection phenomena in 2DEGs. Our findings pave the way to in situ tunable optoelectronics combining concepts from the infrared and terahertz spectral regions.

Source: ACS Photonics

DOI: 10.1021/acsphotonics.6c01501

Authors: Ran Chen, Matthew Tan, Harvey E. Beere, Jonathan P. Griffiths, David A. Ritchie, Wladislaw Michailow

Institutions: Chinese Academy of Sciences, University of Cambridge, Swansea University

Language: English

Topic: Terahertz technology and applications

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,500

Funders: Cambridge Trust, China Scholarship Council, Engineering and Physical Sciences Research Council, Trinity College, University of Cambridge