Photonic Crystal Composites with Reversible High-Frequency Stop Band Shifts


  • The authors thank DARPA (Grant Number: N66001-01-1-8938), NASA/EPScOR (Grant Number: NCC5-575), and the 3M Corporation through a Non-Tenured Faculty Award (SF) for financial support.


The fabrication of photonic crystal composites composed of encapsulated electrostatically stabilized colloidal arrays with tailorable thermomechanical properties is introduced. Composites with sub-ambient Tg exhibited reversible mechanochromic characteristics and a 172 nm stop-band tuning range, and could be modulated up to frequencies of 200 Hz. The Figure shows reflective characteristics of the composites at different strain levels (see also inside front cover).