Anisotropy of electronic lifetime in indium

Electronic lifetimes limited by the electron-phonon interaction are calculated on both the second-and third-zone Fermi surfaces in indium for temperatures 0.1-10 K. Pseudopotential models for the true Fermi surface, electronic band velocity, many-OPW (orthogonalized plane wave) electronic wave function, phonon spectra, and the electron-phonon interaction are used in this calculation. The electron-phonon matrix elements are evaluated by a Monte Carlo method, and the inverse life-time τ^-1(→k) is calculated in terms of the Eliashberg function α²F(→k,ω). T³ behavior of τ^-1(→k) is obtained only on free-electron-like regions and at low temperatures, as expected. Deviation from the T³ dependence is found near the ridges of the Fermi surface. A huge anisotropy (30: 1 at 3 K) in γ(→k), the T³ coefficient of τ^-1(→k), is found over the second-zone surface, with minimum values on the free-electron-like regions and maximum values on the ridges. Quantitative agreement with experiment for γ(→k) in the [111] direction on the second-zone surface (a free-electron-like region) is obtained. Good agreement is also found for the orbit-averaged scattering rate at 4 K with the experiments of Hoff et al. However, our local scattering rate is more peaked with larger values on the ridges of the second-zone surface than the local values extracted by Hoff et al. from their orbit-averaged results by an inversion scheme, indicating that their inversion scheme is not correct. Our orbit-averaged results on the third-zone surface are not in as good agreement with the experiments of Hoff et al. (differing by as much as 20-40%) as are the results on the second-zone surface.