| 초록 |
Colloidal self-assembly is one of the most promising method to prepare photonic bandgap materials due to fast and inexpensive fabrication process. However, photonic bandgap tuning of colloidal crystals remains as a tough problem. In this study, we report reversible photonic bandgap tuning of colloidal crystals under electric field. For this, we synthesized highly charged polystyrene particles through emulsion polymerization by adding ionic comonomer, 3-allyloxy-2-hydroxy-1-propanesulfonic acid. When the charged particles are dispersed in polar medium, they formed face-centered cubic structures. Lattice spacing of colloidal crystals were controlled by electrophoretic movement of colloidal particles under alternating current field. Finally, photonic bandgap was reversibly tuned up to 40 nm for 15000 V/m. |
