Novel optically responsive and diffracting materials derived from crystalline colloidal array self-assembly

Novel tunable and switchable diffracting devices useful in the UV, visible and IR region are fabricated through self assembly of monodisperse, highly charged colloidal particles into crystalline colloidal arrays (CCA). The particles form BCC or FCC arrays with spacings that diffract light. We fabricated devices where the particle size or spacing changes with temperature to tune the diffraction. We also fabricated nonlinear devices which switch in similar to 3 ns. This CCA utilizes dyed particles, which are index matched to the medium. No light is diffracted at low intensities, but at high intensities the particles heat up, their index mismatches from the medium to turn the CCA diffraction on within 5 ns.