title: Asymmetric split H-shape nanoantennas for molecular sensing.
abstract: In this paper we report on a very sensitive biosensor based on gold asymmetric nanoantennas that are capable of enhancing the molecular resonances of C-H bonds. The nanoantennas are arranged as arrays of asymmetric-split H-shape (ASH) structures, tuned to produce plasmonic resonances with reflectance double peaks within the mid-infrared vibrational resonances of C-H bonds for the assay of deposited films of the molecule 17β-estradiol (E2), used as an analyte. Measurements and numerical simulations of the reflectance spectra have enabled an estimated enhancement factor on the order of 105to be obtained for a thin film of E2 on the ASH array. A high sensitivity value of 2335 nm/RIU was achieved, together with a figure of merit of approximately 8. Our experimental results were corroborated using numerical simulations for the C-H stretch vibrational resonances from the analyte, superimposed on the plasmonic resonances of the ASH nanoantennas.
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
authors.forename: I G
authors.initials: IG
authors.lastname: Mbomson
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
authors.forename: S
authors.initials: S
authors.lastname: Tabor
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
authors.forename: B
authors.initials: B
authors.lastname: Lahiri
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
authors.forename: G
authors.initials: G
authors.lastname: Sharp
authors.affiliation: School of Computing and Engineering, Glasgow Caledonian University, Glasgow, G4 0BA, UK.
authors.forename: S G
authors.initials: SG
authors.lastname: McMeekin
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
authors.forename: R M
authors.initials: RM
authors.lastname: De La Rue
authors.affiliation: School of Engineering, University of Glasgow, Glasgow, G12 8LT, UK.
authors.forename: N P
authors.initials: NP
authors.lastname: Johnson
keywords: (130.6010) Sensors; (250.5403) Plasmonics