Fabrication and characterization of two-photon polymerized features in colloidal crystals

The fabrication and characterization of two-photon polymerized features written within and outside of colloidal crystals is presented. Two-photon polymerization (TPP) response diagrams are introduced and developed to map the polymerization and damage thresholds for features written via modulated beam rastering. The use of tris[4-(7-benzothiazol-2-yl-9,9-diethylfluoren-2-yl) phenyl]amine (AF-350) as an initiator for TPP is demonstrated for the first time and TPP response diagrams illustrate the polymerization window. These diagrams also demonstrate that the polymerization behavior within and outside of colloidal crystals is similar and electron microscopy reveals nearly identical resolution. Fluorescence confocal microscopy further enables visualization of non-self-supporting, three-dimensional TPP features within self-assembled photonic crystals. Finally, microspot spectroscopy is collected from a two-photon feature written within a colloidal crystal and this is compared with simulation.