物理系12月1日seminar

报告题目： Surface States Dominated Infrared Conductivity in a Topological Crystalline Insulator 报告人：李志强，四川大学报告时间： 12月1日（星期四） 10:30AM 报告地点：清华大学物理系理科楼三楼报告厅（C302）摘要： The novel physical properties of topological crystalline insulators (TCIs) make them a versatile platform for exploring topological phenomena and potential applications. However, progress in this field has been hindered by the challenge to probe the optical and transport properties of the surface states. In this talk I’ll report our infrared study of a TCI, (001) oriented Pb0.7Sn0.3Se in zero and high magnetic fields. We demonstrate that the far-infrared conductivity is dominated by the surface states as a result of their unique band structure and the consequent high surface carrier density. Moreover, our experiments yield a surface mobility of 40,000 cm2 V-1 s-1. The transport parameters obtained from our experiments suggest the viability of surface-dominated conduction in thin TCI crystals. These findings open up new opportunities for exploring the exotic physics predicted for TCIs.