Current dependent reorganization in superconducting Y1Ba2Cu3O7-δ

We present strong non-linear dynamic responses developing due to magnitude and type of driving current in bulk polycrystalline superconducting Y1Ba2Cu3O7-δ sample at zero magnetic field. Several novel types of dynamic changes induced by the transport current were observed via the time evolution of the voltage (V - t  curves). The physical observations appearing in V - t curves were interpreted mainly with the reorganization of driving current in a multiply connected network of weak-link structure. It was found that such a dynamic process could cause an enhancement or suppression in superconducting order parameter due to the magnitude of the driving current and coupling strength of weak link structure together with the chemical and anisotropic states of the sample. It was shown that the general behavior of decays evolving in V - t curves is consistent with an exponential relation which is analogous to the glassy state relaxation.