Tunable Bragg peak response in liquid-crystal-infiltrated photonic crystals

We report the dependence of the first-order Bragg peak position and width on the liquid-crystal and backbone refractive indices for liquid-crystal-infiltrated large-pore inverse shell opals, which offer increased volume for electro-optic infiltration. We also present the dependence of the photonic response on the template architecture or liquid-crystal volume fraction, which can be manipulated with a multilayer atomic layer deposition process. It is demonstrated from a three-dimensional finite-difference time-domain band structure and transmission-reflection coefficients computations that certain large-pore architectures exhibit an unusual optical response that cannot be explained by a classical Bragg peak theory. These structures potentially offer a pathway for all-optical photonic switching devices. (c) 2007 Optical Society of America.