Scattering mechanisms of surface electrons in topological insulators
Taras Shevchenko National University of Kyiv Volodymyrska st., 60, Kiev, 01033, Ukraine
Kyiv Academic University, 36 Academician Vernadsky Blvd., Kyiv 03142, Ukraine
G.V. Kurdyumov Institute for Metal Physics, National Academy of Sciences of Ukraine 36 Academician Vernadsky Blvd., Kyiv 03142, Ukraine
Received May 14, 2018, revised August 3, 2018, published online November 26, 2018
The uniqueness of topological insulators is in the presence of the topologically protected quasiparticle surface states, which are exceptionally resistant to presence of impurities, nevertheless the structure of the scattering spectrum of topological quasiparticles is not well studied. The aim of the work — determination of the surface states self-energy from photoemission spectra analysis. In particular, the binding energy dependence of the broadening of these states has been studied in detail in Bi2Se3 and Bi2Te2Se — the most explored topological insulators. The revealed stair-structure of the broadening made it possible to distinguish the contributions of the elastic and inelastic interband scattering (surface to bulk) to quasiparticle self-energy and to show that these contributions are comparable with the elastic intraband scattering.
Key words: topological insulator, ARPES spectrum, electron scattering.