Bistability in voltage-biased normal-metal/insulator/superconductor/insulator/normal-metal structures

摘要: As a generic example of voltage-driven superconducting structure, we study short superconductor connected to normal leads by means low transparency tunnel junctions with voltage bias V between the leads. The order parameter ? is be determined self-consistently. We stationary states as well dynamics after perturbation. system an dissipative driven nonlinear system. Such systems generically have solutions that are multivalued functions parameters. It was discovered several decades ago superconductors outside equilibrium conform this general rule in function driving may multivalued. main difference these previous studies and present work different relaxation mechanisms involved. This does not change fact there can at given voltage. however affect their stability find region space where two stable These bistable distinguished distinct values current evaluated (1) V, (2) (3) critical which superconductivity island ceases. With regards dynamics, numerical evidence only no complicated nonstationary regime induced changing result somewhat unexpected trivial, out equilibrium. response always gradual even interaction strength induces rapid anharmonic oscillations parameter.