Experimental study of the anisotropic electron-phonon interaction in A1

Abstract From analysis of surface-Landau-level resonance in the (110) sample plane of A1, we have determined the Fermi velocity and electron-phonon scattering rate at three characteristic locations on the Fermi surface. Using the measured velocities and calculated band velocities we extract local values of the electron-phonon enhancement factor λ. A γ T 3 temperature dependence is found for the scattering rate with γ varying by a factor 8 for the three Fermi surface locations. The experimental results are compared with recent theoretical calculations.