Spin-coating of designed functional planar defects in opal film: Generalized synthesis

A method for spin coating of nanometer scale colloidal photonic crystals (CPC) or opals defect layers from a wide variety of polymers, doped polymers, or particles that are dissolved in hydrophobic solvents was examined. This method was used to demonstrate fluorescent defects with strongly modulated light output and a mechanically tunable CPC incorporating an elastomeric planar defect. The CPC voids were filled with a suitable sacrificial material to prevent the infiltration of the cladding opal layer during the spin coating process. The filling material was removed after the spin coating of the defect ant the next CPC was grown on top to complete the structure. A structure enabled by this spin coating approach was a CPC bearing an elastomeric defect layer, allowing for active mechanical tuning of the defect wavelength. Results show a general and facile bottom up method for the incorporation of planar defects in CPC by spin coating.