Self-consistent modelling of nonlinear dynamic ESM microscopy in mixed ionic-electronic conductors

TL;DR

This paper models the nonlinear dynamic response of mixed ionic-electronic conductors in electrochemical strain microscopy using a self-consistent approach based on Thomas-Fermi screening and Vegard law, revealing charge wave phenomena and surface deformation.

Contribution

It introduces a self-consistent numerical model for nonlinear dynamic ESM in mixed ionic-electronic conductors, accounting for steric effects and charge wave formation.

Findings

Numerical maps of strain and concentration distributions were generated.

Surface displacements under bias were quantified.

Results can inform the design of memory devices using ionic-electronic materials.

Abstract

Dynamic Electrochemical Strain Microscopy (ESM) response of mixed ionic-electronic conductors is analysed in the framework of the Thomas-Fermi screening theory and Vegard law with accounting of the steric effects. The emergence of dynamic charge waves and nonlinear deformation of the surface as result of applying probing voltage is numerically explored. 2D maps of the strain and concentration distribution across the mixed ionic-electronic conductor and bias-induced surface displacements for ESM microscopy were calculated. Obtained numerical results can be of applied to quantify ESM response of Li-based solid electroytes, materials with resistive switching and electroactive ferroelectric polymers, which are of potential interest for flexible and high-density non-volatile memory devices.