Abstract
Initial nonlogarithmic (t<t) stages of flux creep in superconductors have been studied both theoretically and experimentally. Measurements of the time constant τ in grain-oriented at T=20 K and B=6 T and various sweep rates /dt are presented. The experimental data as well as an analysis of nonlinear flux diffusion for different flux-creep models indicate that the constant τ is a macroscopic quantity essentially depending upon initial conditions and sample geometry. The value τ is shown to be inversely proportional to the sweep rate with τ reaching 5× s at /dt=5× Ts.
- Received 23 September 1991
DOI:https://doi.org/10.1103/PhysRevB.44.12090
©1991 American Physical Society