Field and temperature dependence of thermally activated flux flow resistance in Tl2Ba2CaCu2O8 thin films

The field and temperature dependence of thermally activated flux flow (TAFF) resistance in Tl 2 Ba 2 CaCu 2 O 8 thin films (one film being c -axis-oriented and the other 20° tilted from c -axis) has been measured. By analyzing the broadening of the resistive transition with the TAFF model, we get the field and temperature dependence of the activation energy U c ( T , H ) for flux motion of both pancake and Josephson vortices, which is described by U c ( T , H ) = A (1 − t ) H − n with A a constant and t = T / T c ′ ( T c ′ ≈ T c ) .