electrode*

We study the resistive switching in tunnel junctions with single-crystal La₂NiO₄ electrodes. Such electro-resistive devices are promising candidates for future nonvolatile memory and reconfigurable logic applications thanks to their simple structure, scalability and endurance. Our tunnel junctions were prepared by painting a spot of conductive silver epoxy on the surface of La₂NiO₄ single crystal. The interface between the silver and the semiconducting single crystal served as a natural barrier forming planar normal metal/insulator/semiconductor (N-I-S) tunnel junctions with resistances ranging from a few tens to tens of thousands of Ohms. The current-voltage measurements performed on such junctions at room temperature demonstrated a bias-driven resistive switching with ratios above 1000% and high endurance. In situ measurements with two junctions (N-I-S-I-N) demonstrate the polarity-dependent resistive switching of the two (N-I-S and S-I-N) junctions and show no contribution from the bulk of the La₂NiO₄ crystal. Such an interfacial nature of the switching phenomenon is promising for fabrication of thin-film planar devices to be used in nonvolatile memory and logic.