Proximity effects in topological insulator heterostructures

• Published in: Chinese physics B Vol. 22; no. 9; pp. 84 - 92
• Main Author: 李晓光 张谷丰 武光芬 陈铧 Dmmitrie Culcer 张振宇
• Format: Journal Article
• Language: English
• Published: 01.09.2013
• Subjects: Control systems; Foundations; Helical; Heterostructures; Insulators; Phase diagrams; Proximity effect (electricity); Surface reactions; Topology; 垂直位置; 应用程序; 异质结构; 拓扑; 物理现象; 第一性原理; 绝缘体; 邻近效应
• ISSN: 1674-1056; 2058-3834; 1741-4199
• DOI: 10.1088/1674-1056/22/9/097306

Topological insulators （Tls） are bulk insulators that possess robust helical conducting states along their interfaces with conventional insulators. A tremendous research effort has recently been devoted to TI-based heterostructures, in which con- ventional proximity effects give rise to a series of exotic physical phenomena. This paper reviews our recent studies on the potential existence of topological proximity effects at the interface between a topological insulator and a normal insu- lator or other topologically trivial systems. Using first-principles approaches, we have realized the tunability of the vertical location of the topological helical state via intriguing dual-proximity effects. To further elucidate the control parameters of this effect, we have used the graphene-based heterostructures as prototypical systems to reveal a more complete phase diagram. On the application side of the topological helical states, we have presented a catalysis example, where the topo- logical helical state plays an essential role in facilitating surface reactions by serving as an effective electron bath, These discoveries lay the foundation for accurate manipulation of the real space properties of the topological helical state in TI- based heterostructures and pave the way for realization of the salient functionality of topological insulators in future device applications.