Lei, M.
, Migliori, A.
and Ledbetter, H.
(1999),
Acoustic Evidence Against BCS Behavior in Monocrystal YBa<sub>2</sub>Cu<sub>3</sub>0<sub>7</sub>, Physica C-Superconductivity and Its Applications
(Accessed October 20, 2025)
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Acoustic Evidence Against BCS Behavior in Monocrystal YBa2Cu307
Published
Author(s)
M Lei, Albert Migliori,
Abstract
Using a detwinned YBa2Cu307 monocrystal and acoustic-resonance spectroscopy, we measured internal friction Q- = A If through the 91-K superconducting-transition temperature. We show measurements for the first ten macroscopic resonance frequencies fr None of the modes show classic BCS-model behavior based on simple-pairing, isotropic-s-electron, weak-coupling assumptions. Beside being non-BCS-like, essentially every mode behaves differently, suggesting a stronly anisotropic energy gap δ(k), andpractically ruling out any simple Fermi-surface gap function, especially s-wave.Some modes actually show increasing Q-1 upon cooling below Tc, suggesting either strong Fermi-surface changes or lattice-relation mechanisms.Citation
Physica C-Superconductivity and Its Applications
Volume
C 282-287
Pub Type
Journals
Keywords
acoustic, internal friction, monocrystal, superconductor, YBa<sub>2</sub>Cu<sub>3</sub>0<sub>7</sub>
Citation
Issues
If you have any questions about this publication or are having problems accessing it, please contact [email protected].
Created October 31, 1999, Updated October 12, 2021