Color Rendering Plasmonic Aluminum Substrates with Angular Symmetry Breaking.
We fabricate and characterize large-area plasmonic substrates that feature asymmetric periodic nanostructures made of aluminum. Strong coupling between localized and propagating plasmon resonances leads to characteristic Fano line shapes with tunable spectral positions and widths. Distinctive colors spanning the entire visible spectrum are generated by tuning the system parameters, such as the period and the length of the aluminum structures. Moreover, the asymmetry of the aluminum structures gives rise to a strong symmetry broken color rendering effect, for which colors are observed only from one side of the surface normal. Using a combination of immersed laser interference lithography and nanoimprint lithography, our color rendering structures can be fabricated on areas many inches in size. We foresee applications in anticounterfeiting, photovoltaics, sensing, displays, and optical security.
CSEM SA, Thin Film Optics , Muttenz 4132, Switzerland.|ETH Zürich, Photonics Laboratory , Zürich 8093, Switzerland.
Luc
L
Duempelmann
CSEM SA, Thin Film Optics , Muttenz 4132, Switzerland.
Daniele
D
Casari
CSEM SA, Thin Film Optics , Muttenz 4132, Switzerland.
Angélique
A
Luu-Dinh
CSEM SA, Thin Film Optics , Muttenz 4132, Switzerland.
Benjamin
B
Gallinet
ETH Zürich, Photonics Laboratory , Zürich 8093, Switzerland.
Lukas
L
Novotny
Fano line shape; aluminum; angle-dependent; immersed laser interference lithography; plasmonics; structural colors; symmetry breaking