Low-temperature vortex state of the high-Tc superconductor Bi2Sr2Ca2Cu3O10 in high magnetic fields

We report detailed measurements of current-voltage characteristics for a Bi2Sr2Ca2Cu3O10/Ag tape immersed in liquid neon (27 K) and in liquid oxygen (5490 K) as a function of applied magnetic field up to 17 T. It is found that the electric-field-versus-current-density (E-J) curves can be well described by the relation E/Jexp[-(J0/J)], where J0 is a constant. The exponent at elevated temperature (T54 K) is less than 0.9, and is inconsistent with the vortex-glass description, which predicts <1. At low-temperature (T=27 K), a plateau in the value of (1.45) is found for 2H8 T, which may be described by the collective creep theory at this temperature and field range.