Quantum interference between dark-excitons and zone-edged acoustic phonons in few-layer WS₂.

ABSTRACT: Fano resonance which describes a quantum interference between continuum and discrete states, provides a unique method for studying strongly interacting physics. Here, we report a Fano resonance between dark excitons and zone-edged acoustic phonons in few-layer WS₂ by using the resonant Raman technique. The discrete phonons with large momentum at the M-point of the Brillouin zone and the continuum dark exciton states related to the optically forbidden transition at K and Q valleys are coupled by the exciton-phonon interactions. We observe rich Fano resonance behaviors across layers and modes defined by an asymmetry-parameter q: including constructive interference with two mirrored asymmetry Fano peaks (weak coupling, q > 1 and q < - 1), and destructive interference with Fano dip

SUBMITTER: Tan QH 

PROVIDER: S-EPMC9816112 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature