Magnetic-field gradients in the mixed state of a type-II superconductor are studied using Tl205 nuclear magnetic resonance (NMR) on Tl2Ba2Ca2Cu3O10+δ. An anomalous peak was observed in the temperature dependence of the transverse relaxation rate at T/Tc0.25. We attribute this behavior to magnetic-field flucutations from vortex dynamics. We interpret this behavior as a crossover of the principal time scale for vortex dynamics with that of the NMR experiment, approximately 100 μs. The temperature dependence of this time scale is discussed.
ASJC Scopus subject areas
- Condensed Matter Physics