Double resonance in the system of coupled Josephson junctions

The effect of LC shunting on the phase dynamics of coupled Josephson junctions has been examined. It has been shown that additional (rc) branches appear in the current-voltage characteristics of the junctions when the Josephson frequency omega(J) is equal to the natural frequency of the formed resonance circuit omega(rc). The effect of the parameters of the system on its characteristics has been studied. Double resonance has been revealed in the system at omega(J) = omega(rc) = 2 omega(LPW), where omega(LPW) is the frequency of a longitudinal plasma wave appearing under the parametric-resonance conditions. In this case, electric charge appears in superconducting layers in the interval of the bias current corresponding to the rc branch. The charge magnitude is determined by the accuracy with which the double resonance condition is satisfied. The possibility of the experimental implementation of the effects under study has been estimated.