Circularly polarized images with contrast reversal using pseudo-chiral metasurfaces
Résumé
Anticounterfeiting technologies rely on visual effects that are specific to particular structures and concealed to the unwary observer. Plasmonic nanostructures are one solution to these two requirements, and besides colored effects, the possibility to design covert images in a particular polarization state of light is particularly appealing. The generation of circular polarization provides a new degree of freedom, and the use of pseudochiral plasmonic resonators hosting magnetoelectric resonances allows tailoring opposite handedness of circular polarization within the same nanostructure. In this work, we have defined a palette of luminance observable only in circular dichroism by engineering the shapes and positions of the resonators. The spatial control of the polarization state of light is highlighted by realizing a micrometer-scale image revealed only in circular polarization with an additional contrast reversal associated with circular dichroism reversal.
Domaines
Physique [physics]Origine | Fichiers produits par l'(les) auteur(s) |
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