Oscillatory magnetic relaxation in Bi2Sr2CaCu2O8+delta

Time-resolved magneto optical measurements in Bi2Sr2CaCu2O8+delta show oscillatory relaxation of the local magnetization. The oscillatory behaviour is observed in a limited range of temperatures and fields below the vortex order-disorder phase transition line. We ascribe this phenomenon to coupled effects of thermally activated flux creep and annealing of transient disordered vortex states injected into the sample during field increase. (c) 2007 Elsevier B.V. All rights reserved.