Plasmonics have been actively explored for the structural colour printing applications owing to their preferential photon absorption and scattering. To date, many schemes have been demonstrated for the realization of full colour pixels employing various plasmonic geometries. However the quest for a perfect plasmonic geometry that offers pure colour pixels with distinct reflective peaks and high colour saturation combined with low cost and high throughput scalable fabrication is not yet fulfilled. We propose a scheme for generating all colours from violet to red in the visible spectrum with high colour purity and saturation by a clever engineering of concomitant multiple plasmonic resonances in 2D arrays of aluminum based nano antennas. In order to realize vivid full colour pixels, we fabricated 2D arrays of aluminum nano squares raised on top of PMMA nano posts in the back ground of a perforated back reflector by systematically varying the square size (D) and periodicity (P). In the single layer fabrication process the PMMA nano posts were defined by electron beam lithography and subsequently aluminum thin film was deposited by thermal evaporation to form both the nano squares and the fishnet like back reflector. The colour formation is based on the excitation of plasmonic light absorption at two distinct wavelengths leaving a central reflective peak that is coherently scattered by coupling to a strongly radiating dipole resonance. Pure colours both in the RGB and CMY colour schemes with extreme reflective peaks of high quality factor (FWHM of 100nm) across the visible spectrum are demonstrated.

Date Published: 28 April 2017
PDF: 1 pages
Proc. SPIE 10112, Photonic and Phononic Properties of Engineered Nanostructures VII, 101121B (28 April 2017); doi: 10.1117/12.2251627

Published in SPIE Proceedings Vol. 10112:
Photonic and Phononic Properties of Engineered Nanostructures VII
Ali Adibi; Shawn-Yu Lin; Axel Scherer, Editor(s)