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The submitted manuscript has been created by the University of Chicago as Operator of Argonne National Laboratory ("Argonne") under Contract No. W-31-1 09-ENG-38 with the U.S. Department of Energy. The U.S. Government retains for itself, and others acting on its behalf, a paid-up, nonexclusive, irrevocable worldwide ficense in said article to reproduce, prepare derivative works, distribute copies to the pubfic, and perform publicly and display publicly, by or on behalf of the Government.

The absence of a Lorentz force dependence on dissipation in the highly anisotropic high-temperature superconductor, T12Ba2CaCu20x, has been measured over a wide range of current densities in broadened resistive transitions, current-voltage characteristics, magnetoresistances, and critical current densities, Jc. The magnetoresistances are very use.fu1 to find out the correct temperature and field dependences of the activation energy. As an alternative to flux motion, we consider a Josephson-coupling model which is consistent with the broadened resistive transitions and the lack of Lorentz-force dependence. We found that the Josephsoncoupling model agrees with the temperature dependences of the activation energy and J, and is better matched to the weak field dependence of Jc than the flux creep model. Possible origins of Josephson junctions in high-quality films and single crystals are discussed.

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