Osaka - Until now, the metamaterials used to create tunable color from structural geometry have been based on metals.
Although effective in achieving high resolutions, metallic materials suffer from inherent energy losses at visible wavelengths, which makes optimizing color purity challenging.
A trio of researchers at Osaka University recently demonstrated precise color control using monocrystalline silicon.
The metamaterial arrays feature nanoscale patterns that function as antennae, which convert optical radiation into localized energy.
Electron beam lithography was used to create masks, which were used to protect the silicon surface from subsequent plasma etching.
The team was able to generate vivid colors controlled completely by the geometry of the antennae, also demonstrating white light generation, which is important for full-color printing.