ASYMPTOTIC STATES IN LONG JOSEPHSON-JUNCTIONS IN AN EXTERNAL MAGNETIC-FIELD

Asymptotic states in long Josephson junctions are investigated in an e xternal magnetic field. We show that a choice of the solution of the s tationary Ferrell-Prange equation can be carried out with use of an as ymptotic solution of the sine-Gordon equation and that an evolution to that stable solution occurs by passing through metastable states, whi ch is determined with a form of quickly damped initial perturbation. T he boundary sine-Gordon and Ferrell-Prange problems were carried out w ith a numerical simulation. An approximated expression for the vortex and antivortex states is obtained in the case of large values of an ex ternal magnetic field.