An Oxygen Vacancy Memristor Ruled by Electron Correlations

• Published in: Advanced science Vol. 9; no. 27; pp. e2201753 - n/a
• Main Authors: Humbert, Vincent, El Hage, Ralph, Krieger, Guillaume, Sanchez‐Santolino, Gabriel, Sander, Anke, Collin, Sophie, Trastoy, Juan, Briatico, Javier, Santamaria, Jacobo, Preziosi, Daniele, Villegas, Javier E.
• Format: Journal Article
• Language: English
• Published: Germany John Wiley & Sons, Inc 01.09.2022; Wiley Open Access
• Subjects: Electronics; Electrons; Engineering Sciences; Interfaces; memristors; Metals; Micro and nanotechnologies; Microelectronics; neuromorphic systems; nickelates; Oxidation; Oxygen; Phase transitions; Single crystals; strongly correlated electrons; Temperature; Transmission electron microscopy; memristors; neuromorphic systems; nickelates; strongly correlated electrons
• ISSN: 2198-3844; 2198-3844
• DOI: 10.1002/advs.202201753

Resistive switching effects offer new opportunities in the field of conventional memories as well as in the booming area of neuromorphic computing. Here the authors demonstrate memristive switching effects produced by a redox‐driven oxygen exchange in tunnel junctions based on NdNiO3, a strongly correlated electron system characterized by the presence of a metal‐to‐insulator transition (MIT). Strikingly, a strong interplay exists between the MIT and the redox mechanism, which on the one hand modifies the MIT itself, and on the other hand radically affects the tunnel resistance switching and the resistance states' lifetime. That results in a very unique temperature behavior and endows the junctions with multiple degrees of freedom. The obtained results bring up fundamental questions on the interplay between electronic correlations and the creation and mobility of oxygen vacancies in nickelates, opening a new avenue toward mimicking neuromorphic functions by exploiting the electric‐field control of correlated states. A reversible oxygen exchange at the interface between an amorphous metal (Mo80Si20) and a strongly correlated oxide (NdNiO3, NNO) yields strong resistive switching effects. Interestingly the metal‐to‐insulator transition characteristic of NNO interplays with that redox mechanism, leading to a very unique behavior that opens new avenues for mimicking neuromorphic functions by exploiting the electric‐field control of correlated states.