Hussain Ghulam, Fakhredine Amar, Islam Rajibul, Sattigeri Raghottam M, Autieri Carmine, Cuono Giuseppe
International Research Centre MagTop, Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02668 Warsaw, Poland.
Institute of Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02668 Warsaw, Poland.
Materials (Basel). 2023 Feb 16;16(4):1649. doi: 10.3390/ma16041649.
The appearance of intrinsic ferromagnetism in 2D materials opens the possibility of investigating the interplay between magnetism and topology. The magnetic anisotropy energy (MAE) describing the easy axis for magnetization in a particular direction is an important yardstick for nanoscale applications. Here, the first-principles approach is used to investigate the electronic band structures, the strain dependence of MAE in pristine VSiZ (Z = P, As) and its Janus phase VSiGePAs and the evolution of the topology as a function of the Coulomb interaction. In the Janus phase the compound presents a breaking of the mirror symmetry, which is equivalent to having an electric field, and the system can be piezoelectric. It is revealed that all three monolayers exhibit ferromagnetic ground state ordering, which is robust even under biaxial strains. A large value of coupling J is obtained, and this, together with the magnetocrystalline anisotropy, will produce a large critical temperature. We found an out-of-plane (in-plane) magnetization for VSiP (VSiAs), and an in-plane magnetization for VSiGePAs. Furthermore, we observed a correlation-driven topological transition in the Janus VSiGePAs. Our analysis of these emerging pristine and Janus-phased magnetic semiconductors opens prospects for studying the interplay between magnetism and topology in two-dimensional materials.
二维材料中本征铁磁性的出现为研究磁性与拓扑结构之间的相互作用开辟了可能性。描述特定方向上磁化易轴的磁各向异性能量（MAE）是纳米级应用的一个重要衡量标准。在此，采用第一性原理方法来研究电子能带结构、原始VSiZ（Z = P，As）及其Janus相VSiGePAs中MAE的应变依赖性以及作为库仑相互作用函数的拓扑结构演变。在Janus相中，该化合物呈现出镜面对称性的破坏，这等同于存在一个电场，并且该系统可能具有压电性。结果表明，所有这三个单层都表现出铁磁基态有序性，即使在双轴应变下也很稳定。获得了较大的耦合J值，并且这与磁晶各向异性一起将产生较高的临界温度。我们发现VSiP（VSiAs）具有面外（面内）磁化，而VSiGePAs具有面内磁化。此外，我们在Janus相VSiGePAs中观察到了关联驱动的拓扑转变。我们对这些新出现的原始和Janus相磁性半导体的分析为研究二维材料中磁性与拓扑结构之间的相互作用开辟了前景。
