Electron-phonon scattering in topological insulator thin films

We present a theoretical study of electron-phonon scattering effects in thin films made of a strong topological insulator. The phonons are modeled by isotropic elastic continuum theory with stress-free boundary conditions, and the interaction with the helical surface Dirac fermions is mediated by the deformation potential. We determine the temperature-dependent electrical resistivity ρ(T) and the quasiparticle decay rate Γ(T) observable in photoemission. The low- and high-temperature power laws for both quantities are obtained analytically. Detailed estimates covering the full temperature range are provided for Bi₂Se₃.