Lattice dynamics and electron-phonon interaction in Bi/Bi2Te3 (111) heteroepitaxial film
1 Department of Physics, Nanjing Normal University - Nanjing 210023, China
2 National Laboratory of Solid State Microstructures, Nanjing University - Nanjing 210093, China
Received: 28 September 2013
Accepted: 28 November 2013
Bi/Bi2Te3 (111) heteroepitaxial film is a novel system which combines two-dimensional and three-dimensional topological insulators. The lattice dynamical properties and the electron-phonon coupling in this heteroepitaxial film are calculated by including spin-orbit coupling from density functional perturbation theory. Full phonon dispersion curves are calculated and the zone-center Raman active modes are analyzed. There is a large mismatch in the phonon densities of states between ultrathin Bi deposited layers and Bi2Te3 substrate, which might have a significant improvement of thermoelectric performance of this system. The large electron-phonon coupling λ in Bi/Bi2Te3 heteroepitaxial film suggests that this system may hopefully become a topological superconductor.
PACS: 71.70.Ej – Spin-orbit coupling, Zeeman and Stark splitting, Jahn-Teller effect / 68.35.Ja – Surface and interface dynamics and vibrations / 63.20.kd – Phonon-electron interactions
© EPLA, 2013