High refractive index in low metal content nanoplasmonic surfaces from self-assembled block copolymer thin films. Issue 2 (27th November 2018)

• Record Type: Journal Article
• Authors: Alvarez-Fernandez, Alberto; Aissou, Karim; Pécastaings, Gilles; Hadziioannou, Georges; Fleury, Guillaume; Ponsinet, Virginie
• Is Part Of: Nanoscale advances. Volume 1:Issue 2(2019)
• Page Start: 849
• Page End: 857
• Publication Date: 2018-11-27
• Subjects: 620.5
• DOI: 10.1039/c8na00239h
• Languages: English
• ISSNs: 2516-0230

Abstract

Abstract : Block copolymer-templated gold nanostructured surfaces of high refractive index due to controlled plasmonic nanoparticle shape. Abstract : Materials with a high and tunable refractive index are attractive for nanophotonic applications. In this contribution, we propose a straightforward fabrication technique of high-refractive index surfaces based on self-assembled nanostructured block copolymer thin films. The selective and customizable metal incorporation within out-of-plane polymer lamellae produces azimuthally isotropic metallic nanostructures of defined geometries, which were analysed using microscopy and small-angle X-ray scattering techniques. Variable-angle spectroscopic ellipsometry was used to relate the geometrical parameters of the metallic features and the resulting refractive index of the patterned surfaces. In particular, nanostructured gold patterns with a high degree of homogeneity and a gold content as low as 16 vol% reach a refractive index value of more than 3 in the visible domain. Our study thus demonstrates a new route for the preparation of high refractive index surfaces with a low metal content for optical applications.