Tuneable photonic crystals obtained by liquid crystal infiltration



The unique combination of fluidity and birefringence that is characteristic for liquid crystals is quite suitable in order to tune the optical properties of photonic crystals. Here, some experimental examples are reviewed where colloidal crystals (artificial opals and inverse opals), two- and three-dimensional photonic crystals made of macroporous silicon and photonic crystal fibres have been filled with liquid crystals and the changes of their optical properties due to temperature variation or external fields have been investigated. The performance and limits of state-of-the-art photonic crystals filled with liquid crystals are discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)