PHASE-LOCKING OF FLUXONS IN SPATIALLY INHOMOGENEOUS JOSEPHSON-JUNCTIONS

We use a simple perturbative approach to study phase locking dynamics of a fluxon in a long Josephson junction in the presence of a periodic spatial inhomogeneity. We derive an analytical expression for the cur rent size of the phase-locked step as a function of the system's param eters, which is valid in the ultra-relativistic limit. We find that ou r analysis is in good agreement with direct numerical simulations of t he collective-coordinate description of the full system. (C) 1997 Publ ished by Elsevier Science B.V.