A group of scientists have created a new kind of pixel, over a million times smaller than OLED’s found in phone screens, opening up opportunities for new kinds of display and microscopic technologies.
The breakthrough, announced in the Science Advances journal, highlights how scalable electrically driven colour changing metasurfaces can control plasmonic gaps, filling them with an active medium in a fashion similar to colour changing animals.
During tests, the nanopixels showed strong scattering colours, able to electrically turned across >100-nm wavelength ranges, with energy consumption rates of 9fj per pixel.
The nanopixels showed refresh rates of >50Hz and an optical contrast of >50% during testing, with the report stating that the nanopixels can be scaled “from the single nanoparticle level to multicentimeter scale films in subwavelength thickness devices”
The report adds “Our scheme works by switching the charge state of the entire PANI shell, thus rapidly shifting the resonant scattering colour of the eNPoM across >100-nm wavelength ranges.
“This active nanopixel only requires ~0.2 fJ of energy for each 1-nm shift in wavelength and can achieve commercial video rates (20).
"We show that centimetre-scale eNPoM metasurfaces assembled into disordered patterns by a scalable directed self-assembly scheme show vivid uniform color dynamics, not possible with any existing plasmonic color system.”