Nanowerk September 12, 2024
Fabricating photonic crystals with a complete photonic bandgap in the visible spectrum presents at least two important challenges: achieving a material refractive index > ~2 and a three-dimensional patterning resolution better than ~280 nm. Researchers in Singapore developed a titanium ion-doped resin (Ti-Nano) for high-resolution printing by two-photon polymerization lithography. After printing, the structures were heat-treated in air to induce lattice shrinkage and produced titania nanostructures. The attainted three-dimensional photonic crystals with patterning resolution as high as 180 nm and refractive index of 2.4–2.6. Optical characterization revealed ~100% reflectance within the photonic crystal bandgap in the visible range. They showed capabilities in defining local defects and demonstrated proof-of-principle applications in spectrally selective perfect reflectors and chiral light discriminators… read more. TECHNICAL ARTICLE
Fabrication approach… Credit: Nature Nanotechnology, 9 September 2024