Curvature generation in nematic surfaces

TL;DR

This paper explores methods to induce non-localized Gaussian curvature in thin nematic glass sheets by controlling nematic alignment, enabling programmable shape transformations without relying on topological defects.

Contribution

It introduces a novel approach to generate arbitrary Gaussian curvature in nematic sheets through nematic alignment control, expanding shape programming capabilities.

Findings

Blueprinting of desired Gaussian curvature achieved

Feasible patterns identified for experimental validation

Non-localized curvature generation demonstrated

Abstract

In recent years there has been a growing interest in the study of shape formation using modern responsive materials that can be preprogrammed to undergo spatially inhomogeneous local deformations. In particular, nematic liquid crystalline solids offer exciting possibilities in this context. Considerable recent progress has been made in achieving a variety of shape transitions in thin sheets of nematic solids by engineering isolated points of concentrated Gaussian curvature using topological defects in the nematic director field across textured surfaces. In this paper, we consider ways of achieving shape transitions in thin sheets of nematic glass by generation of non-localised Gaussian curvature in the absence of topological defects in the director field. We show how one can blueprint any desired Gaussian curvature in a thin nematic sheet by controlling the nematic alignment angle across the surface and highlight specific patterns which present feasible initial targets for experimental verification of the theory.