Natural optical activity and its control by electric field in electrotoroidic systems

TL;DR

This paper introduces a new class of electrotoroidic materials that are spontaneously optically active and can have their optical rotation direction switched by an electric field, supported by analytical and first-principles simulations.

Contribution

It proposes the existence of electrotoroidic systems with switchable optical activity, combining analytical derivations, phenomenological insights, and atomistic simulations.

Findings

Materials exhibit spontaneous optical activity.

Electric field can switch the sense of optical rotation.

Atomistic simulations reveal microscopic mechanisms.

Abstract

We propose the existence, via analytical derivations, novel phenomenologies, and first-principles-based simulations, of a new class of materials that are not only spontaneously optically active, but also for which the sense of rotation can be switched by an electric field applied to them-- via an induced transition between the dextrorotatory and laevorotatory forms. Such systems possess electric vortices that are coupled to a spontaneous electrical polarization. Furthermore, our atomistic simulations provide a deep microscopic insight into, and understanding of, this class of naturally optically active materials.