Electron-Phonon Contribution to the Phonon Linewidth in Nb: Theory and Experiment

Abstract
We present theoretical calculations and experimental measurements of the phonon linewidth for Nb. The calculations employ the rigid muffin-tin approximation and a realistic band structure. The measurements were done at low temperature to minimize the contributions to the linewidth from phonon-phonon interactions. The calculations predict and experiments confirm strong electron-phonon coupling for the longitudinal phonon modes in the [110] direction.