Fabrication and characterization of three-dimensional Ta₂O₅/SiO₂photonic crystals

Abstract

Three-dimensional (3D) Ta 2 O 5 /SiO 2 photonic crystals in the visible-violet spectral region are fabricated by an auto-cloning technique on patterned substrates with triangular lattice configurations and their in-plane (the stack XY plane) optical properties are studied. Reflection measurements by normal incidence of light on to the cleaved facet of the photonic crystal reveal maximum reflections at certain photon energies. Comparison with calculated band structure demonstrates that the reflection peaks are either due to the photonic bandgap (PBG) within which the light propagation is forbidden, or due to heavy photons associated with flat bands. A two-step deposition method is adopted to insert luminescent rhodamine 590 into the photonic crystal and the emission property is strongly modified by the photonic crystal. Possible applications of such 3D photonic crystals in optical components are discussed.