School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, People's Republic of China.
ACS Nano. 2012 Feb 28;6(2):1695-701. doi: 10.1021/nn204667z. Epub 2012 Jan 27.
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.
我们通过第一性原理计算研究了 VX(2)(X=S,Se)单层的电子和磁学性质。我们的结果表明， VX(2)单层表现出令人兴奋的铁磁行为，这为原始二维单层中存在磁行为提供了证据。此外，有趣的是，对于 VX(2)单层，无论是磁矩还是磁耦合强度，都随着各向同性应变从-5%到 5%的增加而迅速增加。我们提出应变相关的磁矩与强离子-共价键有关，而铁磁性和磁耦合强度随应变的变化来自于键间和键间相互作用的综合影响。这些发现为设计补充石墨烯的纳米电子器件提供了一种新途径。
