Commensurability Effects in Large Josephson Junctions

Abstract

Two types of commensurability effects are possible in a large Josephson junction patterned with columnar defects. The first occurs for a periodic array of pins when the mean fluxon spacing (tuned by the magnitude of the applied in--plane magnetic field) is a rational fraction of the defect spacing. We show that this effect leads, under fairly general conditions, to a mapping of the behavior of the Josephson junction near the commensurate field values to that of a zero field junction with an effective Josephson penetration depth. The second occurs for more general arrangements of pinning sites, when the orientation of the Josephson vortex lattice (tuned by the direction of the applied field) nearly matches the orientation of the defects. We investigate this tilt response in the limit of a single Josephson vortex. The results are compared, where possible, to recent experiments. As an aside from our main analysis, we prove that, contrary to recent claims in the literature, the critical current density vanishes in the thermodynamic limit, even in the presence of (non--pathologically distributed) pinning disorder

13 pages (REVTeX 3.0). Replaced with version to be published in PRB. 1 uuencoded figure appended. Complete postscript file (including figure) for this paper is available on the World Wide Web at http://cmtw.harvard.edu/~simon/

References in corpus (3)

• Fluctuations and Intrinsic Pinning in Layered Superconductors
• Kinetic Roughening in Surfaces of Crystals Growing on Disordered Substrates
• Dynamic and Static Properties of the Randomly Pinned Planar Flux Array

Cited by in corpus (8)

• The Flux-Line Lattice in Superconductors
• Moving glass theory of driven lattices with disorder
• Dynamical Transition in Sliding Charge-density Waves with Quenched Disorder
• Numerical simulation evidence of dynamical transverse Meissner effect and moving Bose glass phase
• Tilted elastic lines with columnar and point disorder, non-Hermitian quantum mechanics and spiked random matrices: pinning and localization
• Critical currents in Josephson junctions with macroscopic defects
• Driven flux-line lattices in the presence of weak random columnar disorder: Finite-temperature behavior and dynamical melting of moving Bose glass
• Radiation emission due to fluxon scattering on inhomogeneity in large two-dimensional Josephson junction