Energy Gaps and Kohn Anomalies in Elemental Superconductors
Superconductivity
2009-11-13 v1 Strongly Correlated Electrons
Abstract
The momentum and temperature dependence of the lifetimes of acoustic phonons in the elemental superconductors Pb and Nb was determined by resonant spin-echo spectroscopy with neutrons. In both elements, the superconducting energy gap extracted from these measurements was found to converge with sharp anomalies originating from Fermi-surface nesting (Kohn anomalies) at low temperatures. The results indicate electron many-body correlations beyond the standard theoretical framework for conventional superconductivity. A possible mechanism is the interplay between superconductivity and spin- or charge-density-wave fluctuations, which may induce dynamical nesting of the Fermi surface.
Cite
@article{arxiv.0808.1028,
title = {Energy Gaps and Kohn Anomalies in Elemental Superconductors},
author = {P. Aynajian and T. Keller and L. Boeri and S. M. Shapiro K. Habicht and B. Keimer},
journal= {arXiv preprint arXiv:0808.1028},
year = {2009}
}