1 research outputs found
All-Dielectric Full-Color Printing with TiO<sub>2</sub> Metasurfaces
Recently,
color generation in resonant nanostructures have been
intensively studied. Despite of their exciting progresses, the structural
colors are usually generated by the plasmonic resonances of metallic
nanoparticles. Due to the inherent plasmon damping, such plasmonic
nanostructures are usually hard to create very distinct color impressions.
Here we utilize the concept of metasurfaces to produce all-dielectric,
low-loss, and high-resolution structural colors. We have fabricated
TiO<sub>2</sub> metasurfaces with electron-beam lithography and a
very simple lift-off process. The optical characterizations showed
that the TiO<sub>2</sub> metasurfaces with different unit sizes could
generate high reflection peaks at designed wavelengths. The maximal
reflectance was as high as 64% with full width at half-maximum (fwhm)
around 30 nm. Consequently, distinct colors have been observed in
bright field and the generated colors covered the entire visible spectral
range. The detailed numerical analysis shows that the distinct colors
were generated by the electric resonance and magnetic resonances in
TiO<sub>2</sub> metasurfaces. Based on the unique properties of magnetic
resonances, distinct colors have been observed in bright field when
the metasurfaces were reduced to a 4 × 4 array, giving a spatial
resolution around 16000 dpi. Considering the cost, stability, and
CMOS-compatibility, this research will be important for the structural
colors to reach real-world industrial applications