title: Effect of Nanohole Spacing on the Self-Imaging Phenomenon Created by the Three-Dimensional Propagation of Light through Periodic Nanohole Arrays.
abstract: We present a detailed study of the inter-nanohole distance that governs the self-imaging phenomenon created by the three-dimensional propagation of light through periodic nanohole arrays on plasmonic substrates. We used scanning near-field optical microscopy (SNOM) to map the light intensity distributions at various heights above 10×10 nanohole arrays of varying pitch sizes on silver films. Our results suggest the inter-hole spacing has to be greater than the wavelength of the incident light to create the self-imaging phenomenon. We also present Finite-Difference Time-Domain (FDTD) calculations which show qualitative corroboration of our experimental results. Both our experimental and FDTD results show that the self-imaging phenomenon is more pronounced for structures with larger pitch sizes. We believe this self-imaging phenomenon is related to the Talbot imaging effect that has also been modified by a plasmonic component and can potentially be used to provide the basis for a new class of optical microscopes.
authors.affiliation: Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland, School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA.
authors.forename: Mustafa H
authors.initials: MH
authors.lastname: Chowdhury
authors.affiliation: Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities, 200 Union St. SE, Minneapolis, MN 55455, USA ; Department of Physics, Bethel University, 3900 Bethel Drive, St. Paul, MN 55112, USA.
authors.forename: Nathan C
authors.initials: NC
authors.lastname: Lindquist
authors.affiliation: Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities, 200 Union St. SE, Minneapolis, MN 55455, USA.
authors.forename: Antoine
authors.initials: A
authors.lastname: Lesuffleur
authors.affiliation: Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities, 200 Union St. SE, Minneapolis, MN 55455, USA.
authors.forename: Sang-Hyun
authors.initials: SH
authors.lastname: Oh
authors.affiliation: Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland, School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA.
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Lakowicz
authors.affiliation: Center for Fluorescence Spectroscopy, Department of Biochemistry and Molecular Biology, University of Maryland, School of Medicine, 725 West Lombard Street, Baltimore, Maryland 21201, USA.
authors.forename: Krishanu
authors.initials: K
authors.lastname: Ray
keywords: Nanostructures; Near-field microscopy; Plasmonics; Subwavelength structures; Surface plasmons; Talbot and self-imaging effects