Shin Bong Gyu, Park Ji-Hoon, Kong Jing, Jung Soon Jung, Song Young Jae
Department of Nano Science and Technology, Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea.
SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), Suwon, 16419, Republic of Korea.
Adv Mater. 2025 Jul;37(26):e2402373. doi: 10.1002/adma.202402373. Epub 2024 Jul 4.
One of the exotic expectations in the 2D curved spacetime is the geometric potential from the curvature of the 2D space, still possessing unsolved fundamental questions through Dirac quantization. The atomically thin 2D materials are promising for the realization of the geometric potential, but the geometric potential in 2D materials is not identified experimentally. Here, the curvature-induced ring-patterned bound states are observed in structurally deformed 2D semiconductors and formulated the modified geometric potential for the curvature effect, which demonstrates the ring-shape bound states with angular momentum. The formulated modified geometric potential is analogous to the effective potential of a rotating charged black hole. Density functional theory and tight-binding calculations are performed, which quantitatively agree well with the results of the modified geometric potential. The modified geometric potential is described by modified Gaussian and mean curvatures, corresponding to the curvature-induced changes in spin-orbit interaction and band gap, respectively. Even for complex structural deformation, the geometric potential solves the complexity, which aligns well with experimental results. The understanding of the modified geometric potential provides us with an intuitive clue for quantum transport and a key factor for new quantum applications such as valleytronics, spintronics, and straintronics in 2D semiconductors.
二维弯曲时空中一个奇特的预期是二维空间曲率产生的几何势,通过狄拉克量子化,它仍存在尚未解决的基本问题。原子级薄的二维材料有望实现几何势,但二维材料中的几何势尚未通过实验得到确认。在此,在结构变形的二维半导体中观察到了曲率诱导的环形束缚态,并针对曲率效应制定了修正的几何势,该势展示了具有角动量的环形束缚态。所制定的修正几何势类似于旋转带电黑洞的有效势。进行了密度泛函理论和紧束缚计算,其结果与修正几何势的结果在定量上吻合良好。修正几何势由修正高斯曲率和平均曲率描述,分别对应于曲率诱导的自旋轨道相互作用和带隙变化。即使对于复杂的结构变形,几何势也解决了其复杂性,这与实验结果吻合良好。对修正几何势的理解为我们提供了量子输运的直观线索,以及二维半导体中诸如谷电子学、自旋电子学和应变电子学等新量子应用的关键因素。