Kim Bumseop, Shin Dongbin, Namgung Seon, Park Noejung, Kim Kyoung-Whan, Kim Jeongwoo
Graduate School of Semiconductor Materials and Devices Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea.
Department of Physics, Ulsan National Institute of Science and Technology, Ulsan 44919, Korea.
ACS Nano. 2023 Oct 10;17(19):18873-18882. doi: 10.1021/acsnano.3c03893. Epub 2023 Sep 29.
Chiral materials have garnered significant attention in the field of condensed matter physics. Nevertheless, the magnetic moment induced by the chiral spatial motion of electrons in helical materials, such as elemental Te and Se, remains inadequately understood. In this work, we investigate the development of quantum angular momentum enforced by chirality by using static and time-dependent density functional theory calculations for an elemental Se chain. Our findings reveal the emergence of an unconventional orbital texture driven by the chiral geometry, giving rise to a nonvanishing current-induced orbital moment. By incorporating spin-orbit coupling, we demonstrate that current-induced spin accumulation arises in the chiral chain, which fundamentally differs from the conventional Edelstein effect. Furthermore, we demonstrate optoelectronic detection of the orbital angular momentum in the chiral Se chain, providing an alternative to the interband Berry curvature, which is ill-defined in low dimensions.
手性材料在凝聚态物理领域引起了广泛关注。然而,在诸如元素碲(Te)和硒(Se)等螺旋材料中,电子的手性空间运动所诱导的磁矩仍未得到充分理解。在这项工作中,我们通过对元素硒链进行静态和含时密度泛函理论计算,研究了由手性所强制的量子角动量的发展。我们的研究结果揭示了由手性几何驱动的非常规轨道纹理的出现,从而产生了非零的电流诱导轨道矩。通过纳入自旋轨道耦合,我们证明在手性链中会出现电流诱导的自旋积累,这与传统的埃德尔斯坦效应有根本区别。此外,我们展示了在手性硒链中对轨道角动量的光电探测,为在低维度中定义不明确的带间贝里曲率提供了一种替代方法。