Polymeric molds of the layer-by-layer photonic crystal can be economically synthesized with a microtransfer molding technique. The refractive indices of these molds are low, preventing formation of a photonic bandgap. We find that such molds can be conformally coated with higher-index material. Photonic band calculations find structures in which conformally coated layer-by-layer molds have complete bandgaps for both titania and silicon coatings. Large stop bands exist in the 001 stacking direction. Feasibility of experimental conformal coating of the molds has been demonstrated with a titania-coated polyurethane mold, which shows optical features in agreement with simulations of reflection and transmission.
© 2005 Optical Society of America
Rana Biswas, Jinho Ahn, Taeho Lee, Jae-Hwang Lee, Yong-Sung Kim, Chang-Hwan Kim, Wai Leung, Cha-Hwan Oh, Kristen Constant, and Kai-Ming Ho, "Photonic bandgaps of conformally coated structures," J. Opt. Soc. Am. B 22, 2728-2733 (2005)