Electronic structures and magnetic properties of MoS2 nanostructures: atomic defects, nanoholes, nanodots and antidots

摘要

Developing approaches to effectively induce and control the magnetic states is critical to the use of magnetic nanostructures in quantum information devices but is still challenging. Here MoS2-based nanostructures including atomic defects, nanoholes, nanodots and antidots are characterized with spin-polarized density functional theory. The S-vacancy defect is more likely to form than the Mo-vacancy defect due to the form of Mo-Mo metallic bonds. Among different shaped nanoholes and nanodots, triangle ones associated with ferromagnetic characteristic are most energetically favorable, and exhibit unexpected large spin moments that scale linearly with edged length. In particular, S-terminated triangle nanodots show strong spin anisotropy around the Fermi level with a substantial collective characteristic of spin states at edges, enabling it to a desired spin-filtering structure. However, in the antidot, the net spin, coupled order and stability of spin states can be engineered by controlling type and distance of internal nanoholes. Based on the analysis of the spin coupled mechanism, a specific antidot structure, the only S-terminated antidot, was determined to exhibit a large net spin with long-range ferromagnetic coupling above room temperature. Given the recent achievement of graphene- and BN-based nanohole, nanodot and antidot structures, we believe that our calculated results are suitable for experimental verification and implementation opening a new path to explore MoS2-based magnetic nanostructures.