Perturbation theory of superconducting micronetworks near the phase-transition boundary

H.J. FINK; D. RODRIGUES; A. LÓPEZ

PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS

American Physical Society

Año: 1988 vol. 38 p. 8767 - 8777

0163-1829

A perturbation theory for micronetworks is developed which is valid near the second-order phase boundary. Perturbation equations to general order in terms of the nodal order parameter are derived. Explicit corrections to first order in temperature T and magnetic flux φ are obtained from the latter equations. This scheme is then applied to the infinite ladder. Stability limits in terms of the Gibbs free energy are derived for different spatial vortex solutions. Furthermore, the shielding currents of the ladder for ‖φ‖