Non-volatile resistive switching in dielectric superconductor YBCO
  We report on the reversible, nonvolatile and polarity dependent resistive switching between superconductor and insulator states at the interfaces of a Au/YBa$_2$Cu$_3$O$_{7-\delta}$ (YBCO)/Au system. We show that the superconducting state of YBCO in regions near the electrodes can be reversibly removed and restored. The possible origin of the switching effect may be the migration of oxygen or metallic ions along the grain boundaries that control the intergrain superconducting coupling. Four-wire bulk resistance measurements reveal that the migration is not restricted to interfaces and produce significant bulk effects. 
C. Acha and M. J. Rozenberg