Resonances and flux-flow in Josephson junctions

We have studied flux-flow in very long inline Josephson junctions by experiments and numerical simulations. The existence of the phenomenon is evident through the appearance of resistive branches in the current-voltage characteristics. The results are found in very good agreement with the numerical simulations performed on the basis of real experimental parameters, We demonstrate the fundamental difference existing between the experimental evidences of flux-flow and the features generated in the current-voltage characteristic by resonances between em modes in the tunnel barrier and Josephson ac-effect.