Magnetic field of Josephson vortices outside superconductors

Abstract

We consider the structure of Josephson vortices approaching the junction boundary with vacuum in large area Josephson junctions with the Josephson length $λ_J$ large relative to the London penetration depth $λ_L$. Using the stability argument for one-dimentional solitons with respect to 2D perturbations, it is shown that on the scale $λ_J$ the Josephson vortices do not spread near the boundary in the direction of the junction. %, which is in a striking difference with behavior of Abrikosov vortices exiting superconductors. The field distribution in vacuum due to the Josephson vortex is evaluated, the information needed for the Scanning SQUID Microscopy.

5 RevTeX pages, 3 eps figures. The second version includes more detailed explanations and corrections, and slightly modified figures