  Cholesteric liquid crystal elastomers have interesting and potentially very
useful photonic properties. In an ideal monodomain configuration of these
materials, one finds a Bragg-reflection of light in a narrow wavelength range
and a particular circular polarization. This is due to the periodic structure
of the material along one dimension. In many practical cases, the cholesteric
rubber possesses a sufficient degree of quenched disorder, which makes the
selective reflection broadband. We investigate experimentally the problem of
how the transmittance of light is affected by mechanical deformation of the
elastomer, and the relation to changes in liquid crystalline structure. We
explore a series of samples which have been synthesized with photonic stop-gaps
across the visible range. This allows us to compare results with detailed
theoretical predictions regarding the evolution of stop-gaps in cholesteric
elastomers.
