Dielectrowetting of a thin nematic liquid crystal layer

TL;DR

This paper develops a mathematical model for the behavior of thin nematic liquid crystal films under spatially-varying electric fields, predicting their evolution and stability through coupled PDEs and numerical simulations.

Contribution

It introduces a coupled PDE model for NLC film dynamics influenced by electric fields, incorporating molecular orientation and electric potential interactions.

Findings

Electric fields induce instability in NLC films.

The model predicts film evolution under various conditions.

Numerical simulations reveal stability regimes and pattern formation.

Abstract

We consider a mathematical model that describes the flow of a Nematic Liquid Crystal (NLC) film placed on a flat substrate, across which a spatially-varying electric potential is applied. Due to their polar nature, NLC molecules interact with the (nonuniform) electric field generated, leading to instability of a flat film. Implementation of the long wave scaling leads to a partial differential equation that predicts the subsequent time evolution of the thin film. This equation is coupled to a boundary value problem that describes the interaction between the local molecular orientation of the NLC (the director field) and the electric potential. We investigate numerically the behavior of an initially flat film for a range of film heights and surface anchoring conditions.