Exploiting the Photoresponse in LiInP<sub>2</sub>Se<sub>6</sub> for Image Processing.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41941395.
- Also identified by DOI 10.1021/acs.nanolett.5c05227 and PMC identifier 13107444.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
We report an anomalous photoresponse in LiInP<sub>2</sub>Se<sub>6</sub>-gated monolayer MoS<sub>2</sub> field effect transistors (FETs), driven by sub-bandgap photocarrier excitation and relaxation in LiInP<sub>2</sub>Se<sub>6</sub>. The MoS<sub>2</sub>/LiInP<sub>2</sub>Se<sub>6</sub> heterostructure exhibits gate-tunable persistent negative photoconductivity, a rare phenomenon in 2D FET platforms. Notably, the photoconductivity change scales with incident light intensity, with weaker illumination producing slower, smaller responses and stronger illumination inducing faster, stronger suppression. Exploiting the nonlinear, intensity-dependent photoresponse of LiInP<sub>2</sub>Se<sub>6</sub>, we demonstrate an image-processing platform that enables contrast modulation directly at the sensor level. By varying two controllable parameters, namely, applied top-gate bias and light exposure time, the device response can be tuned to modify the contrast of the image. This intrinsic behavior illustrates how contrast tunability can be achieved on a chip, offering a simple and compact route toward elementary preprocessing functions in vision devices.