Evidence of the existence of magnetism in pristine VX _2 monolayers (X = S, Se) and their strain-induced tunable magnetic properties

摘要

First-principles calculations are performed to study the electronic and magnetic properties of VX _2 monolayers (X = S, Se). Our results unveil that VX _2 monolayers exhibit exciting ferromagnetic behavior, offering evidence of the existence of magnetic behavior in pristine 2D monolayers. Furthermore, interestingly, both the magnetic moments and strength of magnetic coupling increase rapidly with increasing isotropic strain from 5% to 5% for VX _2 monolayers. It is proposed that the strain-dependent magnetic moment is related to the strong ionic-covalent bonds, while both the ferromagnetism and the variation in strength of magnetic coupling with strain arise from the combined effects of both through-bond and through-space interactions. These findings suggest a new route to facilitate the design of nanoelectronic devices for complementing graphene.