Nanobatteries in redox-based resistive switches require extension of memristor theory

TL;DR

This paper reveals that nanoionic ReRAM devices function as nanobatteries, requiring an extension of traditional memristor theory to account for non-equilibrium states and non-zero crossing I-V characteristics, impacting future device modeling.

Contribution

The study demonstrates both theoretically and experimentally that nanoionic memristive elements behave as nanobatteries, necessitating an extension of memristor theory to include non-equilibrium states and emf effects.

Findings

Nanoionic memristive devices act as nanobatteries.

Memristor theory must be extended for non-zero crossing I-V curves.

The initial emf depends on material chemistry and transport properties.

Abstract

Redox-based nanoionic resistive memory cells (ReRAMs) are one of the most promising emerging nano-devices for future information technology with applications for memory, logic and neuromorphic computing. Recently, the serendipitous discovery of the link between ReRAMs and memristors and memristive devices has further intensified the research in this field. Here we show on both a theoretical and an experimental level that nanoionic-type memristive elements are inherently controlled by non-equilibrium states resulting in a nanobattery. As a result the memristor theory must be extended to fit the observed non zerocrossing I-V characteristics. The initial electromotive force of the nanobattery depends on the chemistry and the transport properties of the materials system but can also be introduced during ReRAM cell operations. The emf has a strong impact on the dynamic behaviour of nanoscale memories, and thus, its control is one of the key factors for future device development and accurate modelling.