Unconventional Surface Impedance of a Normal-Metal Film Covering a Spin-Triplet Superconductor Due to Odd-Frequency Cooper Pairs
Abstract
We discuss the dynamic response of odd-frequency Cooper pairs to an electromagnetic field. By using the quasiclassical Green function method, we calculate the impedance (Z=R-iX) of a normal-metal thin film which covers a superconductor. In contrast with the standard relation (i.e., R≪X), the impedance in spin-triplet proximity structures shows anomalous behavior (i.e., R>X) in the low frequency limit. This unusual relation is a result of the penetration of odd-frequency pairs into the normal metal and reflects the negative Cooper pair density.
- Publication:
-
Physical Review Letters
- Pub Date:
- August 2011
- DOI:
- 10.1103/PhysRevLett.107.087001
- Bibcode:
- 2011PhRvL.107h7001A
- Keywords:
-
- 74.25.nn;
- 74.45.+c;
- 74.70.-b;
- Proximity effects;
- Andreev effect;
- SN and SNS junctions;
- Superconducting materials