A New Opto-Mechanical Effect in Solids

We propose that large, reversible shape changes in solids, of between $10%--400%$, can be induced optically by photoisomerizing monodomain nematic elastomers. Empirical and molecular analysis of shape change and its relation to thermal effects is given along with a simple model of the dynamics of response. Our experiments demonstrate these effects for the first time and theory is compared qualitatively with our results.