Beijing Key Laboratory of Quantum Devices, Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing, 100871, China.
Center for Nanochemistry, Beijing National Laboratory for Molecular Sciences (BNLMS), College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
Adv Mater. 2019 Oct;31(42):e1903686. doi: 10.1002/adma.201903686. Epub 2019 Sep 6.
Quantum confined devices of 3D topological insulators are proposed to be promising and of great importance for studies of confined topological states and for applications in low-energy-dissipative spintronics and quantum information processing. The absence of energy gap on the topological insulator surface limits the experimental realization of a quantum confined system in 3D topological insulators. Here, the successful realization of single-electron transistor devices in Bi Te nanoplates using state-of-the-art nanofabrication techniques is reported. Each device consists of a confined central island, two narrow constrictions that connect the central island to the source and drain, and surrounding gates. Low-temperature transport measurements demonstrate that the two narrow constrictions function as tunneling junctions and the device shows well-defined Coulomb current oscillations and Coulomb-diamond-shaped charge-stability diagrams. This work provides a controllable and reproducible way to form quantum confined systems in 3D topological insulators, which should greatly stimulate research toward confined topological states, low-energy-dissipative devices, and quantum information processing.
三维拓扑绝缘体的量子限制器件被认为是有前途的，对于研究受限拓扑态以及在低能量耗散的自旋电子学和量子信息处理中的应用具有重要意义。拓扑绝缘体表面不存在能隙，这限制了在三维拓扑绝缘体中实现量子限制系统的实验。在这里，使用最先进的纳米制造技术，成功地在 Bi Te 纳米板中实现了单电子晶体管器件。每个器件由一个受限的中央岛、两个将中央岛与源极和漏极连接的狭窄限制以及周围的栅极组成。低温输运测量表明，这两个狭窄的限制作为隧道结，器件表现出明确定义的库仑电流振荡和库仑钻石形电荷稳定性图。这项工作提供了一种在三维拓扑绝缘体中形成量子限制系统的可控且可重复的方法，这应该极大地促进对受限拓扑态、低能量耗散器件和量子信息处理的研究。
