Exciton Bose-Einstein condensation in transition metal dichalcogenide monolayer under in-plane magnetic fields

Abstract

Based on the Gross-Pitaevskii equation, we theoretically investigate exciton Bose-Einstein condensation (BEC) in transition metal dichalcogenide monolayers (TMDC-MLs) under in-plane magnetic fields. We observe that the in-plane magnetic fields exert a strong influence on the exciton BEC wave functions in TMDC-MLs because of the mixing of the bright and dark exciton states via Zeeman effect. This leads to the brightening of the dark exciton BEC states. The competition between the dipole-dipole interactions (DDI) caused by the long-range Coulomb interaction and the Zeeman effect induced by the in-plane magnetic fields can effectively regulate dark exciton BEC states. Our findings emphasize the utility of TMD-MLs as platforms for investigating collective phenomenon involving excited states.