physica status solidi (b)
D‐Wave Superconductivity Induced Renormalization of Phonons in Strongly Interacting Fermion Systems
Marcin Mierzejewski, J. Zieliński, P. Entel
Abstract
Abstract We have calculated changes in the phonon self‐energy originating from d‐wave superconductivity in the two‐dimensional Hubbard model (U → ∞ limit). Strong local correlations have been incorporated within the mean‐field approximation for auxiliary boson fields. Due to the presence of correlated quasiparticles at the Fermi surface, changes in phonon‐energy shifts and linewidths strongly depend on the concentration of holes. In particular, pronounced effects have been derived for low frequency q = 0 phonons at low doping, where superconductivity starts to set in.