Kyungwha Park

Affiliation

• 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 states which are robust with weak disorder in the presence of time-reversal symmetry, as well as applications to spintronics and thermoelectrics. For device applications, heterostructures have been built and it is critical 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, cases of K adsorption, Bi bilayers, II-VI semiconductors, and a ferromagnetic insulator on Bi₂Se₃, will be discussed.

References

• [1] A. T. Lee, M. J. Han, and K. Park, Magnetic proximity effect at Bi2Se3/EuS interface: electronic structure and spin-orbital texture, Phys. Rev. B 90, 155103 (2014).
• [2] K. Govaerts, K. Park, C. De Beule, B. Partoens, and D. Lamoen, The effect of Bi bilayers on the topological states of Bi₂Se₃: A first-principles study, Phys. Rev. B 90, 155124 (2014).
• [3] K. Park, C. De Beule, and B. Partoens, The ageing effect in topological insulators: evolution of the surface electronic structure of Bi2Se3 upon K adsorption, New J. Phys. 15, 113031 (2013).
• [4] K. Park, J. J. Heremans, V. W. Scarola, and D. Minic, Robustness of topologically protected surface states in layering of Bi₂Te₃ thin films, Phys. Rev. Lett. 105, 186801 (2010).