Tunable magneto-optical properties in MoS2 via defect-induced exciton transitions

Article

关键词: ELECTRON-HOLE EXCITATIONS;    QUASI-PARTICLE;    MONOLAYER MOS2;    QUANTUM LIGHT;    SEMICONDUCTORS;    EMITTERS;   

DOI  :  10.1103/PhysRevB.106.L161407

来源: SCIE

【 摘 要 】

The presence of chalcogen vacancies in monolayer transition metal dichalcogenides (TMDs) leads to excitons with mixed localized-delocalized character and to reduced valley selectivity. Recent experimental advances in defect design in TMDs allow for a close examination of such mixed exciton states as a function of their degree of circular polarization under external magnetic fields, revealing strongly varying defect-induced magnetic properties. A theoretical understanding of these observations and their physical origins demands a predictive, structure-sensitive theory. In this work, we study the effect of chalcogen vacancies on the exciton magnetic properties in monolayer MoS2. Using many-body perturbation theory, we show how the complex excitonic picture associated with the presence of defects-with reduced valley and spin selectivity due to hybridized electron-hole transitions-leads to a structurally controllable exciton magnetic response. We find a variety of g-factors with changing magnitudes and sign depending on the exciton energy and character. Our findings suggest a pathway to tune the nature of the excitons-and by that their magneto-optical properties-through defect architecture.

【 授权许可】

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