Resonant tunneling of light through thin metal films via strongly localized surface plasmons

W.-C. Tan, T. W. Preist, and J. Roy Sambles, Physical Review B, Vol. 62, pp. 11134-11138 (2000). "Copyright © 2000 by the American Physical Society."We present a theoretical model of the optical response of a silver film having narrow-grooved zero-order gratings on both sides. It is found that incident p-polarized photons can resonantly tunnel through such a metal film via exciting standing-wave surface plasmon-polariton (SPP) modes localized in the grooves of the two opposite surfaces. This leads to strong transmission peaks in the visible and ultraviolet regions, while for s-polarized photons the film acts as a nearly perfect mirror

Electromagnetic response of closely spaced metal meshes

Melita Clare Taylor, Alastair P. Hibbins, and J. Roy Sambles, Physical Review B, Vol. 86, article 035126 (2012). Copyright © 2012 by the American Physical SocietyThe electromagnetic transmittance of a double layer of identical square arrays of square holes (mesh) in a perfectly conducting sheet is analytically modeled using a modal matching technique. The structure supports families of standing-wave modes together with surface modes that, close to the onset of diffraction, interact with each other. For frequencies below the onset of diffraction, it is the strength of this interaction mediated by evanescent diffraction in the near fields that dictates the electromagnetic response, which is studied as a function of mesh separation and the lateral misalignment between the meshes

A broadband stripline technique for characterizing relative permittivity and permeability (article)

This is the author accepted manuscript. The final version is available from IEEE via the DOI in this record.The dataset associated with this article is located in ORE at: https://doi.org/10.24378/exe.503We present a stripline design and calibration method allowing the extraction of relative permittivity of single dielectric samples in the 200 MHz – 50 GHz range. The simultaneous extraction of relative permittivity and permeability is also illustrated by characterizing a set of samples comprising magnetic inclusions over the same frequency range. The calibration method involves the use of seven measurements of the stripline scattering parameters (S-parameters) with different length shorts inserted. From these measurements, it is possible to determine the reflections at the transition regions of the stripline to correct the measured S-parameters for characterization. By quantifying a range of samples with increasing percentage volume filling of barium titanate in polyurethane for the case of dielectric samples, and carbonyl iron powder (CIP) for magnetic samples, this work demonstrates a reliable method for the broadband characterization of composite materials.This work was supported by The Engineering and Physical Sciences Research Council (EPSRC) of the United Kingdom and The Defence Science and Technology Laboratory (DSTL) of The United Kingdom, via the EPSRC Center for Doctoral Training in Metamaterials (Grant No. EP/L015331/1

Strong beaming of microwave surface waves with complementary split-ring-resonator arrays (article)

This is the final version of the article. Available from Springer Nature via the DOI in this record.The dataset associated with this article is located in ORE at: https://doi.org/10.24378/exe.584A thin copper sheet, populated by an array of complementary split ring resonators, presents strong surface wave beaming in orthogonal directions at two distinct frequencies. This simple array is significantly thinner than existing single frequency beaming surfaces. The observed beaming frequencies are associated with the two lowest resonance modes of the split rings, and the beams are subwavelength in width and approximately non-diverging. The beaming is analysed through comparison of near-field scans of the surface-normal electric fields with numerical simulations.The authors wish to acknowledge financial support from the Engineering and Physical Sciences Research Council (EPSRC) of the United Kingdom, via the EPSRC Centre for Doctoral Training in Metamaterials (Grant No. EP/L015331/1) and also from QinetiQ

The coupling of microwave radiation to surface plasmon polaritons and guided modes via dielectric gratings

Copyright © 2000 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Journal of Applied Physics 87 (2000) and may be found at http://link.aip.org/link/?JAPIAU/87/2677/1It is shown that an absorbing dielectric layer, sinusoidally modulated in height, on top of a planar metal substrate, may be used to provide coupling between both s- and p-polarized incident microwave photons and surface plasmon polaritons, which propagate along the metal–dielectric interface. The study is carried out using paraffin wax as the dielectric material on an aluminum-alloy plate and the wax is sufficiently thick such that it may also support a guided mode. Energy reradiated from these excited modes into diffracted orders is recorded by monitoring the specular beam reflectivity as a function of wavelength (7.5<λ0<11.3 mm) and azimuthal angle of incidence (0°<φ<90°). The azimuthal-angle-dependent reflectivity scans are fitted using a multilayer, multishape differential formalism to model conical diffraction with a single set of parameters describing the grating profile, and the permittivity and thickness of the wax layer

Draft genome sequences of Phytophthora kernoviae and Phytophthora ramorum lineage EU2 from Scotland.

Newly discovered Phytophthora species include invasive pathogens that threaten trees and shrubs. We present draft genome assemblies for three isolates of Phytophthora kernoviae and one isolate of the EU2 lineage of Phytophthora ramorum, collected from outbreak sites in Scotland.Work in the laboratory of DJS is supported by the BBSRC (BB/ L012499/1 and Nornex). Sequencing was performed by the Exeter Sequencing Service at the University of Exeter, which is supported by Wellcome Trust Institutional Strategic Support Fund (WT097835MF), Wellcome Trust Multi User Equipment Award (WT101650MA) and BBSRC LOLA award (BB/K003240/1)

Genome sequence of Rhodococcus sp. strain PML026, a trehalolipid biosurfactant producer and biodegrader of oil and alkanes

Rhodococcus sp. strain PML026 produces an array of trehalolipid biosurfactant compounds in order to utilize hydrophobic carbon sources, such as oils and alkanes. Here, we report the high-quality draft genome sequence of this strain, which has a total length of 5,168,404 bp containing 4,835 protein-coding sequences, 12 rRNAs, and 45 tRNAs

Optical imaging of the effect of in-plane fields on cholesteric liquid crystals

Sharon A. Jewell and J. Roy Sambles, Physical Review E, Vol. 78, article 012701 (2008). Copyright © 2008 by the American Physical Society.The effects of in-plane electric fields on the director structure of cholesteric liquid crystals has been imaged in three dimensions using fluorescence confocal polarizing microscopy. The results show that a liquid crystal lying outside the electrode gap can be significantly affected by stray fields occurring above the electrode surface, resulting in a 90° rotation of the cholesteric helix. Distinct differences between the behavior of cholesterics with positive and negative dielectric anisotropies are observed

Draft genome sequences of Achromobacter piechaudii GCS2, Agrobacterium sp. Strain SUL3, Microbacterium sp. Strain GCS4, Shinella sp. Strain GWS1, and Shinella sp. Strain SUS2 isolated from Consortium with the Hydrocarbon-Producing Alga Botryococcus braunii.

This is the final version of the article. Available from American Society for Microbiology via the DOI in this record.A variety of bacteria associate with the hydrocarbon-producing microalga Botryococcus braunii, some of which may influence its growth. We report here the genome sequences for Achromobacter piechaudii GCS2, Agrobacterium sp. strain SUL3, Microbacterium sp. strain GCS4, and Shinella sp. strains GWS1 and SUS2, isolated from a laboratory culture of B. braunii, race B, strain Guadeloupe.K.J.J. was funded by a Ph.D. studentship from the Biotechnology and Biologaical Sciences Research Council (BBSRC) LoLa award BB/ K003240/2. The Exeter Sequencing Service was supported by the Wellcome Trust Institutional Strategic Support Fund (WT097835MF), a Wellcome Trust Multi User Equipment Award (WT101650MA), and a BBSRC LoLa award (BB/K003240/2). We gratefully acknowledge the Exeter Sequencing Service and computational core facilities at the University of Exete