Scanning Acousto-Optoelectric Spectroscopy on a Transition Metal Dichalcogenide Monolayer.

ABSTRACT: The charge carrier dynamics are investigated by surface acoustic waves (SAWs) inside a WSe₂ monolayer on LiNbO₃ by scanning acousto-optoelectric spectroscopy. A strong enhancement of the PL emission intensity is observed almost over the entire area of the flake. This enhancement increases with increasing amplitude of the wave and is especially strong at or in the vicinity to defects. The latter is attributed to the SAW-driven Poole-Frenkel activation of trapped charge carriers bound to trapping sites at these defects. In addition, the PL intensity exhibit clear periodic modulations at the SAW's frequency f_SAW and at 2 f_SAW. These modulations are clear and unambiguous fingerprints of spatio-temporal carrier dynamics driven by the SAW. These occur

SUBMITTER: Nysten EDS 

PROVIDER: S-EPMC11619229 | biostudies-literature | 2024 Dec

REPOSITORIES: biostudies-literature