Vortex phase diagram of thin films from magnetoresistance measurements

We have investigated the resistive behavior of (Formula presented) thin films from the Arrhenius form (Formula presented) The effective activation energy, (Formula presented) is compared with the model based on thermally activated flux flow (TAFF), where (Formula presented) In a limited temperature region, (Formula presented) follows the TAFF behavior, and this region is regarded as the pinned liquid state. In the TAFF region, all curves for the effective activation energy for different magnetic fields converge onto one line with a scaling factor (Formula presented) proportional to (Formula presented) The crossover temperature, (Formula presented) separates TAFF from free flux flow. The intermediate region, (Formula presented) where (Formula presented) is the temperature of irreversibility, is called the critical state and is between a pinned liquid and a vortex solid. Finally, based on these analyses, we determine the dynamic vortex phase diagram for different pinning behaviors of the vortex.