posted on 2006-04-12, 12:50authored byRichard Giles, Feodor Kusmartsev
We have determined the ground state for both a ladder array of Josephson junctions and a ladder of thin superconducting wires. We find that the repulsive interaction between vortices falls off exponentially with separation. The fact that the interaction is short-range leads to novel phenomena. The ground state vortex density exhibits a complete devil's staircase as the applied magnetic field is increased, each step producing a pair of metal-insulator transitions. The critical fields in the staircase are all calculated analytically and depend only on the connectivity of the ladder and the area of the elementary plaquette. In particular the normal square ladder contains no vortices at all until the flux per plaquette reaches 0.5/sqrt{3} flux quanta.
History
School
Science
Department
Physics
Pages
133532 bytes
Publication date
1999
Notes
This is a pre-print. It is also available at: http://arxiv.org/abs/cond-mat/9903383.