An Ultra-Thin Near-Perfect Absorber via Block Copolymer Engineered Metasurfaces

Cian Cummins (1, 2, 3) , Quentin Flamant (1) , Ranjeet Dwivedi (1) , Alberto Alvarez-Fernandez (4) , Nils Demazy (2, 3) , Ahmed Bentaleb (1) , Gwenaelle Pound-Lana (5) , Marc Zelsmann (5) , Philippe Barois (1) , Georges Hadziioannou (2, 3) , Alexandre Baron (1) , Guillaume Fleury (2, 3) , Virginie Ponsinet (1)

1 CRPP - Centre de Recherche Paul Pascal
2 LCPO - Laboratoire de Chimie des Polymères Organiques
3 Team 4 LCPO : Polymer Materials for Electronic, Energy, Information and Communication Technologies
4 UCL - University College of London [London]
5 LTM - Laboratoire des technologies de la microélectronique

Producing ultrathin light absorber layers is attractive towards the integration of lightweight planar components in electronic, photonic, and sensor devices. In this work, we report the experimental demonstration of a thin gold (Au) metallic metasurface with near-perfect visible absorption (~ 95 %). Au nanoresonators possessing heights from 5-15 nm with sub-50 nm diameters were engineered by block copolymer (BCP) templating. The Au nanoresonators were fabricated on an alumina (Al2O3) spacer layer and a reflecting Au mirror, in a film-coupled nanoparticle design. The BCP nanopatterning strategy to produce desired heights of Au nanoresonators was tailored to achieve nearperfect absorption at ≈ 600 nm. The experimental insight described in this work is a step forward towards realizing large area flat optics applications derived from subwavelengththin metasurfaces.

Mots clés: Block copolymers; metasurfaces; perfect absorbers; nanoresonators; flat optics

Domaines: Matériaux; Optique / photonique

Cian Cummins, Quentin Flamant, Ranjeet Dwivedi, Alberto Alvarez-Fernandez, Nils Demazy, et al.. An Ultra-Thin Near-Perfect Absorber via Block Copolymer Engineered Metasurfaces. Journal of Colloid and Interface Science, 2022, 609, pp.375-383. ⟨10.1016/j.jcis.2021.11.163⟩. ⟨hal-03547419⟩