Ren Hui-Ying, Mao Yue, Ren Ya-Ning, Sun Qing-Feng, He Lin
Center for Advanced Quantum Studies, School of Physics and Astronomy, Beijing Normal University, Beijing 100875, China.
Key Laboratory of Multiscale Spin Physics, Ministry of Education, Beijing 100875, China.
ACS Nano. 2025 Jan 14;19(1):1352-1360. doi: 10.1021/acsnano.4c13885. Epub 2024 Dec 26.
Introducing quantum confinement has shown promise to enable control of charge carriers. Although recent advances make it possible to realize confinement from semiclassical regime to quantum regime, achieving control of electronic potentials in individual nanoscale quantum dots (QDs) has remained challenging. Here, we demonstrate the ability to tune quantum confined states in individual nanoscale graphene QDs, which are realized by inserting nanoscale monolayer WSe islands in graphene/WSe heterostructures via interfacial engineering. Our experiment indicates that scanning tunneling microscope (STM) tip pulses can trigger a local phase transition in the interfacial nanoscale WSe islands, which, in turn, enables us to tune discrete quantum states in individual graphene QDs. By using a STM tip, we can also generate one-dimensional (1D) position-tunable domain boundaries in the WSe islands. The 1D boundary introduces atomically wide electrostatic barriers that bifurcate quasibound states into two regions in the graphene QD, changing the QD from a relativistic artificial atom to a relativistic artificial molecule.
引入量子限制已显示出有望实现对电荷载流子的控制。尽管最近的进展使得从半经典 regime 到量子 regime 实现限制成为可能，但在单个纳米级量子点（QD）中实现对电子势的控制仍然具有挑战性。在这里，我们展示了在单个纳米级石墨烯量子点中调节量子限制态的能力，这些量子点是通过界面工程在石墨烯/二硒化钨（WSe）异质结构中插入纳米级单层 WSe 岛来实现的。我们的实验表明，扫描隧道显微镜（STM）尖端脉冲可以触发界面纳米级 WSe 岛中的局部相变，这反过来又使我们能够调节单个石墨烯量子点中的离散量子态。通过使用 STM 尖端，我们还可以在 WSe 岛中生成一维（1D）位置可调的畴边界。一维边界引入了原子级宽度的静电势垒，该势垒将准束缚态分成石墨烯量子点中的两个区域，将量子点从相对论性人工原子转变为相对论性人工分子。
