2D Bifurcation diagram of capacitively coupled Josephson junctions in high-Tc superconductors

Abstract

We study the nonlinear dynamics in an array capacitively coupled Josephson junctions with N=3 junctions. We consider the superconductor/ insulator/ superconductor, SIS, type junctions as a model for high temperature superconductors with layered structure. In this study, we introduce the 2D bifurcation diagrams for the Josephson junctions. First we show a current voltage characteristics (CVC) of Intrinsic Josephson Junctions (IJJs) with N=3 Junctions, then we show the breakpoint region,BPR (a region in which a net electric charge appear on superconducting layers, (S-layers), of junctions), in the CVC of the system, then we try to investigate the chaos in BPR region by the 2D bifurcation diagram of the system. We show the 2D bifurcation diagrams in two cases in which either the coupling factor, α or the β parameter which is related to dissipation, be variable. In the later case we showed there is a range of β parameter in which the chaotic region of BPR is disappeared, also we show that there is another range of β in which the BPR structure disappeared.