CURRENT-INDUCED RESISTIVITY HYSTERESIS IN DETWINNED YBA2CU3O7-DELTA SINGLE-CRYSTALS

Resistivity-temperature and voltage-current characteristics of clean d etwinned YBa2Cu3O7-delta single crystals have been measured using a SQ UID picovoltmeter in magnetic fields of up to 5 T. We have observed hy steretic behaviour near T-m in the rho(T) dependence: the resistivity when warming the sample up (the ''superheated'' state) was lower than when cooling it down (the ''supercooled'' state). The V-I characterist ics for the sample in the ''superheated'' and ''supercooled'' states w ere also found to be different. We have found that the ''superheated'' state is unstable and can be switched to the ''supercooled'' state by applying a comparatively low probing current density (j similar to 0. 4 A/cm(2)). We relate the current-induced resistivity hysteresis to th e rearrangment of the solid vortex domains due to the probing current.