Phonon linewidths and electronphonon interaction in Nb
Abstract
We present firstprinciples calculations of the electronphonon contribution to the phonon linewidth in Nb. The calculations employ a realistic band structure and the rigidmuffintin approximation for the electronphonon matrix elements. The calculations predict strong electronphonon coupling for longitudinal phonons propagating in the [110] direction, and for longitudinal phonons of momentum q=0.7(2πa) [100]. The origins of these peaks in the linewidth are discussed in terms of the joint Fermienergy density of states and the symmetry properties of the electronphonon matrix elements. Our results are in agreement with available experimental data concerning the mode and q dependence of the phonon linewidth and with empirical values of the electronphonon coupling constant λ.
 Publication:

Physical Review B
 Pub Date:
 April 1979
 DOI:
 10.1103/PhysRevB.19.3708
 Bibcode:
 1979PhRvB..19.3708B