12 research outputs found
Studies of resistance switching effects in metal/YBa2Cu3O7-x interface junctions
Current-voltage characteristics of planar junctions formed by an epitaxial
c-axis oriented YBa2Cu3O7-x thin film micro-bridge and Ag counter-electrode
were measured in the temperature range from 4.2 K to 300 K. A hysteretic
behavior related to switching of the junction resistance from a high-resistive
to a low-resistive state and vice-versa was observed and analyzed in terms of
the maximal current bias and temperature dependence. The same effects were
observed on a sub-micrometer scale YBa2Cu3O7-x thin film - PtIr point contact
junctions using Scanning Tunneling Microscope. These phenomena are discussed
within a diffusion model, describing an oxygen vacancy drift in YBa2Cu3O7-x
films in the nano-scale vicinity of the junction interface under applied
electrical fields.Comment: To be published in Applied Surface Science
Effect of crystallographic anisotropy on the resistance switching phenomenon in perovskites
Resistance switching effects in metal/perovskite contacts based on epitaxial
c-axis oriented Y-Ba-Cu-O (YBCO) thin films with different crystallographic
orientations have been studied. Three types of Ag/YBCO junctions with the
contact restricted to (i) c-axis direction, (ii) ab-plane direction, and (iii)
both were designed and fabricated, and their current-voltage characteristics
have been measured. The type (i) junctions exhibited conventional bipolar
resistance switching behavior, whereas in other two types the low-resistance
state was unsteady and their resistance quickly relaxed to the initial
high-resistance state. Physical mechanism based on the oxygen diffusion
scenario, explaining such behavior, is discussed.Comment: The final version was published in Journal of Applied Physics (2012