2011/09/30 by Z. -H. Pan, A. V. Fedorov, D. Gardner +3 · 1 citation
Physics and Astronomy · #cond-mat.str-el #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevlett.108.187001
published as Phys. Rev. Lett. 108, 187001 (2012) · published version, 5 pages, 4 figures
arxiv created 2013/01/08 · arxiv updated 2013/01/09
Gapless surface states on topological insulators are protected from elastic scattering on non-magnetic impurities which makes them promising candidates for low-power electronic applications. However, for wide-spread applications, these states should have to remain coherent at ambient temperatures. Here, we studied temperature dependence of the electronic structure and the scattering rates on the surface of a model topological insulator, Bi2Se3, by high resolution angle-resolved photoemission spectroscopy. We found an extremely weak broadening of the topological surface state with temperature and no anomalies in the state's dispersion, indicating exceptionally weak electron-phonon coupling. Our results demonstrate that the topological surface state is protected not only from elastic scattering on impurities, but also from scattering on low-energy phonons, suggesting that topological insulators could serve as a basis for room temperature electronic devices.