Effect of crystallographic anisotropy on the resistance switching phenomenon in perovskites

TL;DR

This study investigates how the crystallographic orientation of epitaxial YBCO thin films influences resistance switching in metal/perovskite contacts, revealing orientation-dependent stability of resistance states and proposing an oxygen diffusion mechanism.

Contribution

It is the first to compare resistance switching behavior across different crystallographic orientations in epitaxial YBCO films, highlighting the impact of anisotropy on device stability.

Findings

c-axis oriented junctions show bipolar resistance switching

ab-plane and mixed orientation junctions have unstable resistance states

oxygen diffusion explains the resistance relaxation behavior

Abstract

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.