Nematronics: Reciprocal coupling between ionic currents and nematic dynamics

TL;DR

This paper introduces a spintronics-inspired framework to describe the reciprocal coupling between ionic currents and nematic textures in electrolytes, proposing methods to measure and utilize this interaction for nematronics applications.

Contribution

It develops a phenomenological model for ionic-nematic coupling, deriving equations of motion and proposing impedance-based measurement techniques for the coupling strength.

Findings

Derived equations analogous to spin torque and spin pumping.

Proposed impedance measurement method to quantify coupling.

Illustrated potential functionalities through simple examples.

Abstract

Adopting a spintronics-inspired approach, we study the reciprocal coupling between ionic charge currents and nematic texture dynamics in a uniaxial nematic electrolyte. Assuming quenched fluid dynamics, we develop equations of motion analogously to spin torque and spin pumping. Based on the principle of least dissipation of energy, we derive the adiabatic "nematic torque" exerted by ionic currents on the nematic director field as well as the reciprocal motive force on ions due to the orientational dynamics of the director. We discuss several simple examples that illustrate the potential functionality of this coupling. Furthermore, using our phenomenological framework, we propose a practical means to extract the coupling strength through impedance measurements on a nematic cell. Exploring further applications based on this physics could foster the development of nematronics -- nematic iontronics.