Fragility of Surface States and Robustness of Topological Order in ${\mathrm{Bi}}_{2}{\mathrm{Se}}_{3}$ against Oxidation

Fragility of Surface States and Robustness of Topological Order in ${Bi}_{2} {Se}_{3}$ against Oxidation

Xiaoxiong Wang, Guang Bian, T. Miller, and T.-C. Chiang

Phys. Rev. Lett. 108, 096404 – Published 29 February 2012

Abstract

Topological surface states are protected against local perturbations, but this protection does not extend to chemical reaction over the whole surface, as demonstrated by theoretical studies of the oxidation of ${Bi}_{2} {Se}_{3}$ and its effects on the surface spin polarization and current. While chemisorption of $O_{2}$ largely preserves the topological surface states, reaction with atomic O removes the original surface states and yields two new sets of surface states. One set forms a regular Dirac cone but is topologically trivial. The other set, while topologically relevant, forms an unusual rounded Dirac cone. The details are governed by the hybridization interaction at the interface.

Received 15 December 2011

DOI:https://doi.org/10.1103/PhysRevLett.108.096404

Authors & Affiliations

Xiaoxiong Wang^1,2,3, Guang Bian^2,3, T. Miller^2,3, and T.-C. Chiang^2,3

¹College of Science, Nanjing University of Science and Technology, Nanjing 210094, China
²Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080, USA
³Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana, Illinois 61801-2902, USA