Dynamical properties of the Josephson multiterminals in an applied magnetic field

Abstract

The nonstationary behaviour of a 4-terminal SQUID is investigated. The studied system presents two coupled microbridges (forming the Josephson multiterminal), one of which is incorporated in a superconducting ring and the other one is connected with a transport circuit. The macroscopic quantum interference, which takes place in the intersection of two microbridges, leads to nonlinear parameteric effects controlled by the external parameters, the applied magnetic flux and the transport current. Within the resistivity shunted junction model the dynamical behaviour of the system is described by three coupled nonlinear differential equations for the phase differences of the order parameter. The time-averaged voltage-current characteristics and the time dependencies of the voltage in the transport circuit and of the induced magnetic flux in the ring are calculated in the current-biased and the voltage-biased regimes. The dependence of the voltage on the applied magnetic flux is obtained for different values of the control current and the self-inductance of the ring.