Australian researchers have developed a technology that could lead to the creation of a non-fading paint for automobiles, buildings and outdoor billboards.
The paint is based on so called plasmonic technology. Plasmons are particles of plasma - ionised gas consisting of positive ions and free electrons and akin to photons - which can be made to oscillate inside nanostructures to produce colours.
The team from the University of Melbourne responsible for creating the technology calls the nanostructures plasmonic pixels. Made of aluminium nanoantennas, the pixels produce specific colours depending on the frequency of the oscillating plasmons.
The technology, described in the latest issue of the journal Nano Letters, provides a much higher number of colours than previously developed plasmonic pixel systems. Images created using the technique can be larger than has been achieved previously, and rely on simpler colour-mapping algorithms. The image created by the Melbourne team is about 1.5cm long.
The technology can produce up to 2000 different colours and shades.
"With the ability to print at resolutions greater than conventional pigment-based processes, the plasmonic pixels may also have applications in security-based devices for use on high-value product packaging, medicines etc," Timothy D James, one of the authors of the study, told Phys.org.
"The immediate goals are further refining the algorithm to increase the colour gamut and saturation, and to investigate the scaled-up fabrication of large-area plasmonic pixel devices with nano-imprint lithography."
This type of plasmonic technology only enables creating static images, unlike systems by other teams that are being developed with the aim to eventually create plasmonic TV screens and phone displays.
The plasmonic-pixel-based image is polarisation-tunable, which means that colours can be switched on and off by changing the direction of the wave oscillation.
Plasmonic systems could also be used to create sensors, light-sources and photovoltaic systems.