Abstract
We report the results of a study of the temperature-dependent thermal difference reflectance spectra of . At temperatures below , a feature emerges in the spectra with an integrated amplitude that scales as , where is the temperature-dependent superconducting gap. The temperature dependence and location of this feature can be described by an Eliashberg model with a coupling function that includes both an electron-phonon interaction and an interaction located at ∼1.6 eV. We find remarkably good agreement between theory and experiment based upon this description of the superconducting state.
- Received 20 May 1994
DOI:https://doi.org/10.1103/PhysRevLett.73.2360
©1994 American Physical Society