METHODS FOR REDUCTION OF FLUX CREEP IN HIGH AND LOW TC TYPE-II SUPERCONDUCTORS

This paper reports the experimental investigations into two different methods of reducing flux creep and magnetic relaxation in high T(c) YBa2Cu3O7 and low T(c) Nb-Ti. For temperatures T less-than-or-equal-to 4.2 k temperature reduction leads to a considerable reduction of the flux creep rate. The second method for reducing relaxation is the choice of appropriate magnetic field cycling prior to measurements being taken. As already found for YBa2Cu3O7, Nb-Ti also shows a strong dependence on magnetic history. These results are of interest for various practical applications.