Microscopic modeling of exciton-polariton diffusion coefficients in atomically thin semiconductors

In the strong light-matter coupling regime realized, e.g., by integrating semiconductors into optical microcavities, polaritons as new hybrid quasiparticles are formed. The corresponding change in dispersion relation has a large impact on optics, dynamics, and transport behavior of semiconductors. this paper, we investigate strong-coupling hBN-encapsulated ${\mathrm{MoSe}}_{2}$ monolayers focusing exciton-polariton diffusion. Applying microscopic approach based exciton density matrix formalism combined with Hopfield approach, predict drastic increase diffusion coefficients two to three orders magnitude regime. We explain much larger polariton group velocity suppressed polariton-phonon scattering channels respect case bare excitons. Our study contributes better understanding atomically thin