We have characterized the vertical transport properties of epitaxial layered
structures composed of Pr0.7Ca0.3MnO3 (PCMO) sandwiched between
SrRuO3 (SRO) bottom electrode and several kinds of top electrodes such as
SRO, Pt, Au, Ag, and Ti. Among the layered structures, Ti/PCMO/SRO is distinct
due to a rectifying current-voltage (I--V) characteristic with a large
hysteresis. Corresponding to the hysteresis of the I--V characteristics,
the contact resistance of the Ti/PCMO interface reversibly switches between two
stable states by applying pulsed voltage stress. We propose a model for the
resistance switching at the Ti/PCMO interface, in which the width and/or height
of a Schottky-like barrier are altered by trapped charge carriers in the
interface states.Comment: 3 pages, 4 figures, Appl. Phys. Lett., in pres