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.Comment: 4 pages, 4 figures, corresponding author: C. Acha ([email protected]

A comparative analysis of

In order to bring new data about the physics of the microscopic \chem{YBa_2Cu_3O_{7-\mathit{x}}} (YBCO) grain boundary mechanism, we have used two different ways to induce modifications in the oxygen sublattice of grain boundary Josephson junctions (GBJs): annealings and irradiation with helium at 80\un{keV} of both electrodes and barrier. We present a comparative study in terms of the main electromagnetic and transport parameters between irradiated and oxygen-deficient junctions with the same critical temperature. In irradiated junctions the coupling energy of the barrier can be enhanced when the superconducting properties of the electrodes are not severely degraded. The modification of the barrier properties depends on the dose and on the particular distribution of the critical current inside the barrier. Changes of the ratio of the relative dielectric constant to the barrier thickness ($\varepsilon/t$) upon irradiation are mainly due to changes in ε, and progress in the same direction as the normal resistance (R_\ab{N}). On the other hand, a reduction of the oxygen content by annealing of YBCO thin film always causes a degradation of the barrier coupling energy. R_\ab{N} increases along with both ε and t