论文标题
内在的轨道力矩和2D过渡金属二分法中大轨道效果的预测
Intrinsic orbital moment and prediction of a large orbital Hall effect in the 2D transition metal dichalcogenides
论文作者
论文摘要
使用轨道电流的生成和检测而不是旋转电流携带信息是一个新兴的研究领域，其中轨道大厅效应（OHE）是重要的成分。在这里，我们提出了一种新的OHE机制，该机制发生在{\ it non-}中心对称材料中。我们表明，在2D过渡金属二分法中（TMDC）中的反转对称性损坏会导致坚固的轨道矩，由于施加的电场下相反的浆果曲率，该轨道矩朝不同方向流动，从而导致大OHE。这与倒置对称系统完全相反，后者仅由外部电场诱导轨道矩。我们表明，即使在没有自旋轨道耦合的情况下，山谷轨道锁定以及OHE都会出现。非零的自旋轨道耦合导致众所周知的山谷旋转锁定和自旋大厅效应，我们认为这很弱，这使得TMDC特别适合直接观察OHE，并且在{\ it Orbitronics}中的潜在应用。
Carrying information using generation and detection of the orbital current, instead of the spin current, is an emerging field of research, where the orbital Hall effect (OHE) is an important ingredient. Here, we propose a new mechanism of the OHE that occurs in {\it non-}centrosymmetric materials. We show that the broken inversion symmetry in the 2D transition metal dichalcogenides (TMDCs) causes a robust orbital moment, which flow in different directions due to the opposite Berry curvatures under an applied electric field, leading to a large OHE. This is in complete contrast to the inversion-symmetric systems, where the orbital moment is induced only by the external electric field. We show that the valley-orbital locking as well as the OHE both appear even in the absence of the spin-orbit coupling. The non-zero spin-orbit coupling leads to the well-known valley-spin locking and the spin Hall effect, which we find to be weak, making the TMDCs particularly suitable for direct observation of the OHE, with potential application in {\it orbitronics}.
