二维拓扑绝缘体薄膜锡烯的MBE原位生长、表征及拓扑性质的调控

二维拓扑绝缘体是一种新的物质态，其在未来低功耗量子器件及容错量子计算中有着广泛应用前景。锡烯因其有着可调控的宽体带隙和非平庸拓扑态在未来拓扑材料实际应用中有着巨大的潜力。然而，目前实验上制备出的锡烯与理想的锡烯相比仍然有着较大的差距，它们大部分呈半金属性，或者没有非平庸的拓扑性。制备出拥有大的体带隙、结构稳定、可在温室下工作的二维拓扑绝缘体目前仍然是一个重要的挑战。在本项目中，我们将利用分子束外延技术，在不同的衬底上制备不同厚度、晶格常数、晶向与不同表面化学修饰的锡烯，以实现对其体带隙及拓扑量子态的调控。同时，我们还将利用扫描隧道显微镜来研究厚度、晶格常数、晶向及表面化学修饰对锡烯薄膜电子结构的影响。这些研究将促进低维拓扑量子领域基础研究的发展与未来新型自旋量子器件的应用。

Two dimensional topological insulator is a new material state, which has a wide application prospect in the future low-power quantum devices and fault-tolerant quantum computing. Stanene has great potential in the application of topological materials in the future due to its wide buck band gap and topological state. However, in recent experiments, there is still a big challenge to prepare stanene with ideal properties，most of them show metallicity or are trivial topological insulator. It is still an important challenge to prepare topological insulator with large buck band gap and can work at room temperature. In this project, we will use molecular beam epitaxy (MBE) technology to prepare stanene with different thickness, lattice constant, crystal orientation and surface chemical modification on different substrates , so as to realize the regulation of its buck band gap and topological quantum state. At the same time, we will also use in-situ scanning tunneling microscopy to characterize the electronic structure of stanene with different thickness, lattice constant, crystal orientation and surface chemical modification. These studies can promote the development of fundamental research and the application of spin quantum devices in the future.