交换场和非共振光对单层MoS2能带结构的调控

基于紧束缚近似下的低能有效哈密顿模型，研究了外部磁近邻交换场和非共振圆偏振光对单层二硫化钼（MoS₂）电子能带结构的调控.研究结果表明，磁近邻交换场能有效调控导带和价带的自旋劈裂，单层MoS₂ K谷附近能隙随着非共振圆偏振光引起的有效能的增大而增大，K′谷附近能隙随着非共振圆偏振光引起的有效能的增大先减小后增大，实现半导体-金属-半导体转变.因而，可以利用磁近邻交换场和非共振圆偏振光将单层MoS₂调制成自旋和光电特性优异的新带隙材料.

Manipulation of the Electronic Band Structure of MonolayerMoS2 in Presence of Exchange Field and Off-Resonant Light

Utilizing the low energy effective Hamilton model from the tight-binding approximation,we have investigated the electronic band structure of the monolayerMoS₂ in the presence of magnetic exchange field and off-resonant circularly polarized light.The obtained results show that,the magnetic exchange field can break and/or modulate the spin degeneracy of the conduction and/or valence bands,and the band gaps around K point of the monolayerMoS₂ increase with the external off-resonant circularly polarized light induced effective energy;while those around K′ increase firstly and then decrease with the light field induced effective energy,realizing the transition of semiconductor-metal-semiconductor.Therefore,the two-dimensionalMoS₂ can be tuned to be new bandgap materials with excellent spin and optoelectrical properties.