论文标题
磁形各向异性在确定单层$ \ mathrm {vsi_2p_4} $的磁性和电子特性方面的重要性
Importance of magnetic shape anisotropy in determining magnetic and electronic properties of monolayer $\mathrm{VSi_2P_4}$
论文作者
论文摘要
二维（2D）铁磁体一直是一个引人入胜的研究主题，而磁各向异性（MA）对于稳定2D磁性阶是必不可少的。在这里，我们通过使用通用梯度近似以及$ u $（gga+$ u $）方法研究了磁各向异性能量（MAE），$ \ mathrm {vsi_2p_4} $的磁性和电子特性。对于大型$ U $，磁性各向异性（MSA）能量对MAE具有更明显的贡献，可以克服磁晶方差（MCA）能量，以证明易于平面。对于固定的平面内MA，单层$ \ MATHRM {VSI_2P_4} $经历Ferrovalley（FV），Half-Valley-Metal（HVM），Valley-Polarized量子异常Hall hall hall hall hall hall hall Inmalous Insulator（vqahi），HVM和FV状态增加，$ u $ $ U $ $ $。但是，对于假设内部的MA，没有特殊的量子异常大厅（QAH）状态和自发山谷范围内的自发山谷极化。根据MAE和电子结构，带有固定的平面外或平面内MA，固有相图显示了单层中的常见磁性半导体（CMS），FV和VQAHI $ \ MATHRM {VSI_2P_4} $。在参考文献中广泛使用的代表性$ u $$ = $ 3，$ \ mathrm {vsi_2p_4} $可以被视为2D- $ xy $磁铁，而不是像以前的作品中预测的类似于2D的长距离订单磁铁，仅考虑MCA能量。我们的发现阐明了MSA在确定单层$ \ mathrm {vsi_2p_4} $的磁性和电子特性中的重要性。
Two-dimensional (2D) ferromagnets have been a fascinating subject of research, and magnetic anisotropy (MA) is indispensable for stabilizing the 2D magnetic order. Here, we investigate magnetic anisotropy energy (MAE), magnetic and electronic properties of $\mathrm{VSi_2P_4}$ by using the generalized gradient approximation plus $U$ (GGA+$U$) approach. For large $U$, the magnetic shape anisotropy (MSA) energy has a more pronounced contribution to the MAE, which can overcome the magnetocrystalline anisotropy (MCA) energy to evince an easy-plane. For fixed out-of-plane MA, monolayer $\mathrm{VSi_2P_4}$ undergoes ferrovalley (FV), half-valley-metal (HVM), valley-polarized quantum anomalous Hall insulator (VQAHI), HVM and FV states with increasing $U$. However, for assumptive in-plane MA, there is no special quantum anomalous Hall (QAH) state and spontaneous valley polarization within considered $U$ range. According to the MAE and electronic structure with fixed out-of-plane or in-plane MA, the intrinsic phase diagram shows common magnetic semiconductor (CMS), FV and VQAHI in monolayer $\mathrm{VSi_2P_4}$. At representative $U$$=$3 eV widely used in references, $\mathrm{VSi_2P_4}$ can be regarded as a 2D-$XY$ magnet, not Ising-like 2D long-range order magnets predicted in previous works with only considering MCA energy. Our findings shed light on importance of MSA in determining magnetic and electronic properties of monolayer $\mathrm{VSi_2P_4}$.
