Nonanalyticity, Valley Quantum Phases, and Light-like Exciton Dispersion in Monolayer TMDs: Theory and First-Principles Calculations

Diana. Y. Qiu, Ting Cao, Steven G. Louie

Exciton dispersion as a function of center-of-mass momentum, \textbf{Q}, is essential to the understanding of exciton dynamics. We use the ab-initio GW-Bethe Salpeter equation meth…