R. G. Herb Condensed Matter Seminars |
Events on Monday, April 8th, 2013
- Fluctuation effects in disordered superconducting films above Tc
- Time: 4:30 pm
- Place: 5310 Chamberlin
- Speaker: Alexander Finkelstein, Weizmann Institute of Science
- Abstract: I will report on the fluctuation corrections in homogeneously disordered superconducting films.
I will start with the Nernst and Hall Effects where fluctuation corrections can be tracked experimentally to temperatures more than order of magnitude above Tc and magnetic fields well above the upper critical field, Hc2(0). There is a quantitative agreement between our theoretical analysis and recent data obtained in conventional superconductors for the Nernst Effect (K. Behnia, France) and the Hall conductivity (Kapitulnik, Stanford) and for the Nernst Effect in certain high-Tc-family materials (L.Taillefer, Canada).
I will also report about our recent calculation of the fluctuation corrections, which is based on the Usadel equation in the real-time formulation. We adjust this approach to derive analytic expressions for the corrections to the longitudinal conductivity in the entire metallic part of the temperature-magnetic field phase diagram. This method allows us to obtain fluctuation corrections in a compact and effective way, establishing a direct connection between phenomenological and microscopic calculations. - Host: Chubukov