Abstract
We derive the effective free energy of a two-dimensional Josephson junction in the presence of an external current and predict that the junction has a phase transition at a temperature TJ below the bulk transition temperature Tc. In the range TJ < T < Tc long-range phase correlation exists in the bulk, but is destroyed in the vicinity of the junction. The critical current Ic is reduced by thermal fluctuations, for a junction of size L, Ic∼ Lb(T) where b(T) < 0 for TJ < T < Tc (i.e. Ic vanishes at L→∞) while 0 < b(T) < 2 for T < TJ. Our results may account for the absence of an observable supercurrent at temperatures below Tc in YBa2Cu3Ox- and Bi2Sr2CaCu2O8-based junctions.
Original language | English |
---|---|
Pages (from-to) | 699-704 |
Number of pages | 6 |
Journal | EPL |
Volume | 25 |
Issue number | 9 |
DOIs | |
State | Published - 20 Mar 1994 |
ASJC Scopus subject areas
- General Physics and Astronomy