Tuning the Frohlich exciton-phonon scattering in monolayer MoS₂.

ABSTRACT: Charge carriers in semiconducting transition metal dichalcogenides possess a valley degree of freedom that allows for optoelectronic applications based on the momentum of excitons. At elevated temperatures, scattering by phonons limits valley polarization, making a detailed knowledge about strength and nature of the interaction of excitons with phonons essential. In this work, we directly access exciton-phonon coupling in charge tunable single layer MoS₂ devices by polarization resolved Raman spectroscopy. We observe a strong defect mediated coupling between the long-range oscillating electric field induced by the longitudinal optical phonon in the dipolar medium and the exciton. This so-called Fröhlich exciton phonon interaction is suppressed by doping. The suppression correlat

SUBMITTER: Miller B 

PROVIDER: S-EPMC6379367 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature