Minimum current and related topics in Josephson tunnel junction devices

Abstract

Soliton return effect in an annular Josephson junction and nonzero minimum voltage and current in the current step Solutions of the equation of motion of Josephson junction devices are approximated by analytical relations in the pronounced nonlinear range of small voltages. The minimum current at which the junction switches back into the net zero voltage state is established for devices with resistive and inductive elements, including the nonlinear tunnel resistance of the junction. The stability of the voltage state is estimated. Conditions for which junctions fail to enter the zero-voltage state are discussed. We obtain the equation of motion by setting all currents Ie __ c R(V) J L FIG. 1. Equivalent circuit of the devices considered here. The element J represents the Josephson current generator 1m sin</>. The other elements include those of the junction in parallel with possible external elements. The resistance which contains the nonlinear tunnel resistance of the junction is voltage dependent.

Josephson dynamics of bicrystald-waveYBa2Cu3O7−Lindström1, Johansson2, Stepantsov3 et al. 2006Phys. Rev. B221200View full textAdd to dashboardCite

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