Magnetization decay and pinning energy in a BSCCO single crystal: a comparison between different methods of measurement

The magnetization decay in a BSCCO single crystal was measured by two different methods: in the first way the decay is observed in the time after stopping the magnetic field, in the second one various hysteresis loops are performed at different field sweep rate. Using these two methods of measurements the authors investigate both flux creep regime, both the thermally assisted flux flow regime and, in the creep regime, they calculated the energy pinning Uo. The two methods give different values: an explanation for this discrepancy is proposed.