Danovich, M. and Aleiner, I. L. and Drummond, N. D. and Fal’ko, V. I. (2017) Fast relaxation of photo-excited carriers in 2-D transition metal dichalcogenides. IEEE Journal of Selected Topics in Quantum Electronics, 23 (1). ISSN 1077-260X
Abstract
We predict a fast relaxation of photo-excited carriers in monolayer transition metal dichalcogenides, which is mediated by the emission of longitudinal optical (LO) and homopolar (HP) phonons. By evaluating Born effective charges for MoS2, MoSe2, WS2, and WSe2, we find that, due to the polar coupling of electrons with LO phonons, and the HP phonons lattice deformation potential, the cooling times for hot electrons and holes from excitation energies of several hundred meV are at ps-scale.