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arXiv · 1910.06398

Plasmonic sensing with FIB-milled 2D micro-arrays of truncated gold nano-pyramids

Filippo Pisano·Antonio Balena·Muhammad Fayyaz Kashif·Marco Pisanello·Antonio Qualtieri·Leonardo Sileo·Tiziana Stomeo·Antonella D'Orazio·Massimo De Vittorio·Ferruccio Pisanello·Marco Grande
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Abstract

Plasmonic platforms are a promising solution for the next generation of low-cost, integrated biomedical sensors. However, fabricating these nanostructures often requires lengthy and challenging fabrication processes. Here we exploit the peculiar features of Focused Ion Beam milling to obtain single-step patterning of a plasmonic two-dimensional (2D) array of truncated gold nano-pyramids (TNP), with gaps as small as 17 nm. We describe the formation of plasmonic bandgaps in the arrangement of crossed tapered grooves that separate the nano-pyramids, and we demonstrate refractive index sensing via dark field imaging in patterned areas of 30 $\mu$m $\times$ 30 $\mu$m.

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Filippo Pisano, Antonio Balena, Muhammad Fayyaz Kashif, Marco Pisanello, Antonio Qualtieri, Leonardo Sileo, Tiziana Stomeo, Antonella D'Orazio, Massimo De Vittorio, Ferruccio Pisanello, Marco Grande. 2019-10-11. Plasmonic sensing with FIB-milled 2D micro-arrays of truncated gold nano-pyramids. https://doi.org/10.1088/1361-6528%2Faba57a

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