Building structures within opal photonic crystals

Engineered defects enhance control over light in photonic crystals. Two novel methods fabricate defects inside polymer opal photonic crystals. The unique abilities of photonic crystals (PCs) to manipulate light lead to potential applications ranging from simple optical switches to an optical computer.1 Researchers are learning how to build PCs with better optical abilities by methods that in-clude designing and fabricating deviations from the regular PC pattern. These deviations—called defects, although they are desirable—can channel light efficiently, but building defects in the structure is challenging. We have developed several methods for defining defect patterns inside of synthetic opal. Opals are naturally occurring 3D PCs: their microstructure consists of silica spheres about 150nm to 300nm in diameter, which are tightly packed into repeating hexagonal or cubic ar-rangements. Synthetic opals use this same pattern, althoug