EXPERIMENTS WITH SOLITONS IN ANNULAR JOSEPHSON-JUNCTIONS

It is known that the long annular Josephson junction allows to avoid t he influence of boundaries and soliton(fluxon)-soliton collisions on t he dynamics of soliton chains. With new experimental methods and junct ion design a fully controlable way of introducing individual solitons into such a system is realized. For the homogeneous junction crossover at high velocities of the fluxon chain is seen and explained in terms of the fluxon bunching. In the periodically modulated junction a new resonant mode called a supersoliton is observed.