Common features of vortex structure in long exponentially shaped Josephson junctions and Josephson junctions with inhomogeneities

摘要

We study vortex structure in three different models of long Josephsonjunctions: exponentially shaped Josephson junction and Josephson junctions withresistor and shunt inhomogeneities in barrier layer. Numerical calculations ofthe possible magnetic flux distributions and corresponding bifurcation curveshave done. For these three models the critical curves ``criticalcurrent-magnetic field'' are constructed. We develop an idea of the equivalenceof exponentially shaped Josephson junction and rectangular junction withdistributed inhomogeneity and demonstrate that at some parameters of shunt andresistor inhomogeneities at the ends of the junction the corresponding criticalcurves are very close to the exponentially shaped one.