论文标题
轨道旋转磁电磁电效应及其单层中的应变工程NB $ x_2 $
Orbital gyrotropic magneto-electric effect and its strain engineering in monolayer Nb$X_2$
论文作者
论文摘要
轨道自由度的电气控制是“轨道人类”新兴领域的重要研究领域。轨道{\ IT陀螺仪}磁电效应（OGME）是通过施加的电场在非磁性金属中产生轨道磁化的。在这里，我们表明，应变在单层NB $ x_2 $（$ x = $ s，se）中引起大型GME，这与飞机正常，主要是由Bloch频段的轨道矩驱动的，而不是传统的自旋磁力化，而无需进行旋转式旋转量的旋转磁力。关键物理被捕获在有效的两频谷 - 轨道模型中，并显示出由三种关键成分驱动的：内在的山谷轨道矩，损坏的$ c_ c_ {3z} $对称性和应变诱导的费米表面变化。效果可以通过改变应变条件而切换，并有可能用于将来的设备应用。
Electrical control of the orbital degrees of freedom is an important area of research in the emerging field of "orbitronics." Orbital {\it gyrotropic} magneto-electric effect (OGME) is the generation of an orbital magnetization in a nonmagnetic metal by an applied electric field. Here, we show that strain induces a large GME in the monolayer Nb$X_2$ ($X =$ S, Se) normal to the plane, primarily driven by the orbital moments of the Bloch bands as opposed to the conventional spin magnetization, without any need for spin-orbit coupling. The key physics is captured within an effective two-band valley-orbital model and it is shown to be driven by three key ingredients: the intrinsic valley orbital moment, broken $C_{3z}$ symmetry, and strain-induced Fermi surface changes. The effect can be furthermore switched by changing the strain condition, with potential for future device applications.
