Gradual degradation in the supercurrent state of a chaotic superconducting tunnel junction under time-varying perturbation

摘要

We report on the degradation of the zero-voltage supercurrent generated in a Josephson tunnel junction residing in an asymmetric potential of the ratchet type, and driven by a quasiperiodic external signal having incommensurable frequencies with irrational ratio (omega(2)/omega(1)), equals to the Golden Mean. In the underdamped regime and via computing the current-voltage (I-V) characteristic curves, we demonstrate that the disappearance of the superconducting state can be correlated to chaotic behaviour, where dynamical phase fluctuations and symmetry breakings associated with the potential and modulating signal are substantially taking place. (c) 2005 Elsevier Ltd. All rights reserved.