The apparent T2-temperature dependence of the London penetration depth in Sr2RuO4 is discussed on the basis of a multi-gap model with horizontal line nodes. The influence of the nodes in combination with nonlocal electromagnetic response leads to low-temperature behaviors as - T2ln T in the London limit and as T2 in the Pippard limit. These behaviors appear only at very low temperature. On the other hand, the interplay of the superconductivity of different bands is responsible for the observed T2-like behavior over the wide temperature range. The experimental data can be fitted well with a set of material parameters as was used in the specific-heat fitting.
EPL (Europhysics Letters)
- Pub Date:
- October 2002
- Pairing symmetries;
- Thermodynamic properties;
- Condensed Matter - Superconductivity
- 7 pages, 3 figures in EPL style