Experimental study of fluxon dynamics in long Josephson junctions with a regular lattice of inhomogeneities

An overview of several effects experimentally observed in long quasi-one-dimensional Josephson junctions with an artificially prepared lattice of inhomogeneities is presented. An interaction of fluxons with inhomogeneities gives rise to a variety of new phenomena in Josephson junctions. A fine structure on the first zero-field step due to the radiation of a single fluxon was observed. In the large magnetic field both the effects of pinning and a multi-fluxon flux-flow were studied. In the flux-flow regime two new types of steps appeared in the IV-curves. These steps are explained in terms of Fiske steps synchronization and propagation of defects (supersolitons) in a fluxon chain.