Photogating-assisted tunneling boosts the responsivity and speed of heterogeneous WSe<sub>2</sub>/Ta<sub>2</sub>NiSe<sub>5</sub> photodetectors.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38167874.
- Also identified by DOI 10.1038/s41467-023-44482-7 and PMC identifier 10762006.
- 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
Photogating effect is the dominant mechanism of most high-responsivity two-dimensional (2D) material photodetectors. However, the ultrahigh responsivities in those devices are intrinsically at the cost of very slow response speed. In this work, we report a WSe<sub>2</sub>/Ta<sub>2</sub>NiSe<sub>5</sub> heterostructure detector whose photodetection gain and response speed can be enhanced simultaneously, overcoming the trade-off between responsivity and speed. We reveal that photogating-assisted tunneling synergistically allows photocarrier multiplication and carrier acceleration through tunneling under an electrical field. The photogating effect in our device features low-power consumption (in the order of nW) and shows a dependence on the polarization states of incident light, which can be further tuned by source-drain voltages, allowing for wavelength discrimination with just a two-electrode planar structure. Our findings offer more opportunities for the long-sought next-generation photodetectors with high responsivity, fast speed, polarization detection, and multi-color sensing, simultaneously.