Nematic liquid crystal flow driven by time-varying active surface anchoring

TL;DR

This paper explores how time-varying active surface anchoring influences flow regimes in nematic liquid crystals, demonstrating tunable flow behaviors through numerical simulations with potential applications in photonics and active matter.

Contribution

It introduces a numerical study of nematic liquid crystal flows driven by dynamic surface anchoring, revealing diverse flow regimes and tunable flow properties based on anchoring parameters.

Findings

Different flow regimes depend on anchoring direction and phase.

Flow magnitude can be tuned by cell thickness and frequency.

Diverse flow behaviors include no-net, oscillatory, steady, and pulsating flows.

Abstract

We demonstrate the generation of diverse material flow regimes in nematic liquid cells as driven by time-variable active surface anchoring, including no-net flow, oscillatory flow, steady flow, and pulsating flow. Specifically, we numerically simulate a passive nematic fluid inside a cell bounded with two flat solid boundaries at which the time-dependent anchoring is applied with the dynamically variable surface anchoring easy axis. We show that different flow regimes emerge as the result of different anchoring driving directions (i.e. co-rotating or counter-rotating) and relative phase of anchoring driving. The flow magnitude is tunable by cell thickness and anchoring driving frequency. More generally, this work aims towards possible applications of responsive time-variable surfaces, including photonics or synthetic active matter.