Physics – Condensed Matter
Scientific paper
1993-06-08
Physics
Condensed Matter
18 pages (revtex) + 11 figures (upon request), NSF-ITP-93-76
Scientific paper
10.1103/PhysRevB.50.1190
I present the detailed behavior of phonon dispersion curves near momenta which span the electronic Fermi sea in a superconductor. I demonstrate that an anomaly, similar to the metallic Kohn anomaly, exists in a superconductor's dispersion curves when the frequency of the phonon spanning the Fermi sea exceeds twice the superconducting energy gap. This anomaly occurs at approximately the same momentum but is {\it stronger} than the normal-state Kohn anomaly. It also survives at finite temperature, unlike the metallic anomaly. Determination of Fermi surface diameters from the location of these anomalies, therefore, may be more successful in the superconducting phase than in the normal state. However, the superconductor's anomaly fades rapidly with increased phonon frequency and becomes unobservable when the phonon frequency greatly exceeds the gap. This constraint makes these anomalies useful only in high-temperature superconductors such as $\rm La_{1.85}Sr_{.15}CuO_4$.
No associations
LandOfFree
Kohn Anomalies in Superconductors does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Kohn Anomalies in Superconductors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Kohn Anomalies in Superconductors will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-185994