论文标题
应变工程和磁性在单层中的隐藏作用VTE $ _2 $
Strain engineering and the hidden role of magnetism in monolayer VTe$_2$
论文作者
论文摘要
二维过渡金属二分法最近引起了极大的关注。在最近对Crystalline Bulk VTE $ _2 $的研究中，我们从理论上研究了单层VTE $ _2 $中的旋转电荷晶体相互作用。为了了解有关几个不同电荷密度波接地状态的有争议的实验报告，我们特别注意抗铁磁性的“隐藏”作用，因为其直接的实验检测可能具有挑战性。我们的第一原理计算表明，4 $ \ times $ 1的电荷密度波和相应的晶格变形伴随着“双条纹”抗磁性自旋顺序，处于其基态。该阶段不仅具有最低的总能量，而且具有动态声子稳定性，该稳定性支持先前的一组实验。有趣的是，仅通过假设基础旋转顺序才能稳定这种基态。通过注意到磁性和其他自由度之间的这种有趣且以前未知的相互作用，我们进一步提出了可能的应变工程。通过施加拉伸应变，单层VTE $ _2 $首先表现出相变为不同的电荷密度波相，然后最终到达铁磁有序。
Two-dimensional transition metal dichalcogenides have attracted great attention recently. Motivated by a recent study of crystalline bulk VTe$_2$, we theoretically investigated the spin-charge-lattice interplay in monolayer VTe$_2$. To understand the controversial experimental reports on several different charge density wave ground states, we paid special attention to the 'hidden' role of antiferromagnetism as its direct experimental detection may be challenging. Our first-principles calculations show that the 4$\times$1 charge density wave and the corresponding lattice deformation are accompanied by the 'double-stripe' antiferromagnetic spin order in its ground state. This phase has not only the lowest total energy but also the dynamical phonon stability, which supports a group of previous experiments. Interestingly enough, this ground state is stabilized only by assuming the underlying spin order. By noticing this intriguing and previously unknown interplay between magnetism and other degrees of freedom, we further suggest a possible strain engineering. By applying tensile strain, monolayer VTe$_2$ exhibits phase transition first to a different charge density wave phase and then eventually to a ferromagnetically ordered one.
