Date and Time:  31-May-2022  10:00AM

Speaker:  Dr. Su Kong Chong, University of California, Los Angeles

Host: Peng Deng (BAQIS）

Title: Quantum Transport in Topological Insulator based Van Der Waals Heterostructures

Abstract: 

The discovery of linear-dispersive topological surface states in three-dimensional topological insulators has offered a platform to study the topological phases in Dirac materials. Different from conventional 2D electron gas and Dirac fermions, the topological surface states are a manifestation of their bulk band inversion and exhibit a unidirectional spin texture locked to their momenta. In this talk, I will present my research on the quantum transport properties of two-closely related system, (i) intrinsic 3D TIs, Bi2-xSbxTe3-ySey, and (ii) magnetic TIs, Crx(Bi,Sb)2Te3. I will introduce a van der Waals (vdW) heterostructures platform which we invented to control and manipulate the topological phases in these two materials in a feasible and efficient manner. The similarity and difference between the two materials, particularly their quantum Hall states or quantum anomalous Hall states, originating from the non-trivial topological surface states will be discussed in the talk.

About the Speaker:

Dr. Su Kong Chong is a postdoctoral scholar at Department of Electrical and Computer Engineering, UCLA. He is working with Prof. Kang L. Wang on the magnetic and transport properties of magnetic topological insulators and semimetals, with a focus of the electrical control of the magnetic and topological phases. He earned his Ph.D. degree in Physics from University of Utah, under supervision of Prof. Vikram Deshpande. His PhD dissertation focused on the topological insulator thin films and heterostructures.