One Dimensional Electronic Structure Studies on Monolayer MoS₂ Grain Boundaries

On the boundary of the material, low dimensional electronic states, which are localized on the boundary, can be created. In this research, we have investigated grain boundaries of monolayer MoS₂ as a platform of one-dimensional (1D) physics. We have studied the electronics structures by density-functional theory calculations. We have designed a specific atomic structure of the boundary so that defect states show significantly low bandwidth, comparing to the bulk band. Due to low bandwidth, electrons can create spin or charge order on the boundary. Magnetism is obtained when electron doped case, which can be realized by MoS₂/Graphene heterojunction. Energetically the system favors antiferromagnetism compared to ferromagnetism. These magnetic orders solely derived from electronic structure instabilities. In addition to that, charge density wave can also be formed on the boundary of the grains. Our research suggests possibility of 1D interacting electrons on transition metal dichalcogenide grain boundaries.