Dynamical regimes of kinematic vortices in the resistive state of a mesoscopic superconducting bridge
Alice Presotto, Edson Sardella, André Luiz Malvezzi, Rafael Zadorosny
Abstract
Abstract In this work, we studied the dynamics of the kinematic vortices (kV) in a mesoscopic superconductor under the influence of external applied magnetic fields ( H ) and transport currents ( J tr ). A J tr ( H ) phase diagram is determined. We show that the vortex dynamics are profoundly affected by the presence of constrictions and by H . We find that between the Meissner and normal states, the resistive state is comprehended by three distinct states. One of these states is a kinematic vortex–antivortex pair for low values of H . For moderate values of fields, the kV state is unpaired and only a single kinematic vortex exists. In the high field regime, the kinematic vortex becomes an Abrikosov-like state with a lower velocity. It was also shown that for tenths of picoseconds, a surface barrier effect acts over the instantaneous velocity of the kV.