Gaussian fluctuations have been observed in the specific heat of two single crystals YBa2Cu3O7. Deviations from a BCS-type step are well accounted for by 3D Gaussian fluctuations whose amplitude ratio, in the cleaner sample, implies that the number of order-parameter components is 7. This result is inconsistent with an O(2) Ginzburg-Landau theory.
ASJC Scopus subject areas
- Physics and Astronomy(all)