TRANSIENT MOMENT RELAXATION IN HIGH-TEMPERATURE SUPERCONDUCTORS

The decays of the persistent supercurrent have been derived for several characteristic I-Y relationships with few sample-dependent parameters. The results are compared with recent short-time flux-creep data in a short "transient" time window (10(-4)-10(2) s). The results favor the I-V characteristics V is-proportional-to exp[-(I0/I)mu], as predicted by the collective-pinning and vortex-glass models. However,the mu so obtained is greater than 1, in contrast with that predicted. This may imply a different type of vortex elemental excitation observed in our low-field conditions.