Magnetization decay due to vortex phase boundary motion in BSCCO

We identify a new regime of decay of the irreversible magnetization in clean Bi 2Sr 2CaCu 2O 8 crystals, at induction values close to the “second peak field” at which the bulk critical current density steeply increases. A time window is identified during which the decay of the induction is controlled by the slow propagation of the phase transformation front across the sample.