Polarization dependence of optically-driven elastomer mechanics.
University of Cambridge
We model how polarized and unpolarized light can cause mechanical response in nematic and
related photo-elastomers. The reduction of order by heating and the consequential large strains
that are known from nematic elastomers can alternatively be caused by light-induced bending of
rodlike dye molecules which then equally reduce the order of their nematic hosts. While there
is no mechanical response to heating of polydomain elastomers, mechanical response to light is
possible by the selective absorption of light according to how domains are aligned with respect to
the polarization direction or with respect to the propagation direction in the case of unpolarized
light. We find large contractions or elongations, depending on the nature of polarization. The responses are non-monotonic with light intensity.