近日，德国雷根斯堡大学Y. A.&Gerasimenko&J.Repp&J. Wilhelm及其研究团队取得一项新进展。经过不懈努力，他们获得了单层晶体中单个空位的超快原子尺度扫描隧穿光谱。相关研究成果已于2024年3月14日在国际知名学术期刊《自然—光子学》上发表。
本文利用光波扫描隧穿显微镜和光谱学，在空间、时间和能量上直接解析了在晶格振动的受控激发下，莫尔畸变的WSe2单层中孤立硒空穴的自旋轨道分裂能级是如何演变的。通过局部激发声子振荡，并拍摄比振动周期更快的空位状态超快能量分辨快照，研究人员直接测量了孤立单原子缺陷中电子-声子耦合的影响。原子空间、亚皮秒时间和毫电子伏能量分辨率的结合，标志着对复杂量子材料全面理解的突破性发展，其中关键的微观基本相互作用现在可以逐一解开。
据悉，原子薄半导体中的缺陷及其莫尔纳米异质结构，已经成为量子科学的一个独特的测试平台。强光-物质耦合、大自旋-轨道相互作用和增强的库仑关联，为未来的量子比特操作和高效的单光子量子发射提供了自旋-光子界面。然而，直接观测单个缺陷的电子结构与其他微观元激发，在其固有长度、时间和能量尺度上的相互作用，至今仍是一个尚未实现的梦想。
附：英文原文
Title: Ultrafast atomic-scale scanning tunnelling spectroscopy of a single vacancy in a monolayer crystal
Author: Roelcke, C., Kastner, L. Z., Graml, M., Biereder, A., Wilhelm, J., Repp, J., Huber, R., Gerasimenko, Y. A.
Issue&Volume: 2024-03-14
Abstract: Defects in atomically thin semiconductors and their moiré heterostructures have emerged as a unique testbed for quantum science. Strong light–matter coupling, large spin–orbit interaction and enhanced Coulomb correlations facilitate a spin–photon interface for future qubit operations and efficient single-photon quantum emitters. Yet, directly observing the relevant interplay of the electronic structure of a single defect with other microscopic elementary excitations on their intrinsic length, time and energy scales remained a long-held dream. Here we directly resolve in space, time and energy how a spin–orbit-split energy level of an isolated selenium vacancy in a moiré-distorted WSe2 monolayer evolves under the controlled excitation of lattice vibrations, using lightwave scanning tunnelling microscopy and spectroscopy. By locally launching a phonon oscillation and taking ultrafast energy-resolved snapshots of the vacancy’s states faster than the vibration period, we directly measure the impact of electron–phonon coupling in an isolated single-atom defect. The combination of atomic spatial, sub-picosecond temporal and millielectronvolt energy resolution marks a disruptive development towards a comprehensive understanding of complex quantum materials, where the key microscopic elementary interactions can now be disentangled, one by one.
DOI: 10.1038/s41566-024-01390-6
Source: https://www.nature.com/articles/s41566-024-01390-6