Thermally Activated Flux Flow Characteristics: MgB2 Tapes

Thermally activated flux flow (TAFF) behavior is studied via magnetoresistance investigations on in situ prepared stainless steel sheathed MgB2 tapes. The thermal activation energy is analyzed using Arrhenius relation and a modified TAFF method. Temperature-dependent prefactor and nonlinear relation of U(H, T) versus T are considered to evaluate apparent activation energy U0. Results from modified TAFF method are found to be in better agreement with experimental data than that from using Conventional Arrhenius method. The results shows that Stainless steel sheathed MgB2 tapes prepared with stoichiometric composition at 800 °C exhibits high U0 of the order of 10
⁵
K.