Speaker: Kyugwha Park, Department of Physics, Virginia Tech, Blacksburg, VA 24060 USA

Title: Proximity effects on topological surface states of Bi2Se3 at non-magnetic and magnetic interfaces from first principles

Abstract:
Topological insulators have drawn a lot of attention due to topologically protected surface-state Dirac cones which are robust over weak disorder in the presence of time-reversal symmetry, as well as to applications for spintronics and thermoelectrics. For device applications, heterostructures have been built and it is crucial to understand how the topological surface states are influenced by various interfaces. In this talk, I will present effects of non-magnetic and magnetic interfaces on the characteristics of the surface-state Dirac cones in three-dimensional topological insulator Bi2Se3, by using first-principles calculations. In particular, theoretical results in cases of K adsorption, Bi bilayers, II-VI semiconductors, and a ferromagnetic insulator on Bi2Se3, will be discussed, as well as their comparison with available experimental data.