Non-linear photo-response of disordered elastomers.
University of Cambridge - Cavendish Lab
We model the polarisation-dependent photo-contractions of polydomain nematic elastomers. Contraction initially arises by light-induced director rotation. At higher light intensity, strain recovers because the local order parameter diminishes. Thus we predict photo-strains non-monotonic with light intensity and the induction of a negative global order parameter for the system of polydomains. Non-monotonic strains would give curvature reversal in thick samples. Our model also predicts an elongational strain response to non-polarised light.