Now showing items 122-136 of 136

  • Surface plasmons on metamaterials 

    Hibbins, Alastair P.; Lockyear, Matthew J.; Sambles, J. Roy (SPIE, 2008)
    The field of plasmonics has historically been a playground exclusively for the optics community. Primarily this is because the response of metals becomes dominated by their large conductivities at much lower frequencies, ...
  • Surface-plasmon-enhanced light scattering from microscopic spheres 

    Jory, M. J.; Cann, P. S.; Sambles, J. Roy; Perkins, E. A. (American Institute of Physics, 2003)
    The enhanced light scattering from microscopic latex spheres placed in the optical field associated with a surface-plasmon resonance is explored. Spheres of 200 nm diameter are placed on an optically thin gold film that ...
  • Surface-topography-induced enhanced transmission and directivity of microwave radiation through a subwavelength circular metal aperture 

    Lockyear, Matthew J.; Hibbins, Alastair P.; Sambles, J. Roy; Lawrence, Christopher R. (American Institute of Physics, 2004)
    Strongly enhanced transmission of microwave radiation (λ0~5 mm) is observed through a single subwavelength circular aperture of diameter d = 2.5 mm in a metallic plate. The phenomenon is caused by resonant excitation of ...
  • Thin resonant structures for angle and polarization independent microwave absorption 

    Lockyear, Matthew J.; Hibbins, Alastair P.; Sambles, J. Roy; Hobson, Peter A.; Lawrence, Christopher R. (American Institute of Physics, 2009)
    We present a microwave absorbing structure comprised of an array of subwavelength radius copper disks, closely spaced from a ground plane by a low loss dielectric. Experiments and accompanying modeling demonstrate that ...
  • Time-resolved sign-dependent switching in a hybrid aligned nematic liquid crystal cell 

    Taphouse, T. S.; Cornford, Stephen Leslie; Birkett, J. E.; Sambles, J. Roy (Institute of Physics and Deutsche Physikalische Gesellschaft, 2008)
    An optical waveguide technique is used to determine the director tilt profile across a hybrid aligned nematic (HAN) liquid crystal cell, in which the optical response is dependent on the sign of the applied voltage. Two ...
  • Transition from localized surface plasmon resonance to extended surface plasmon-polariton as metallic nanoparticles merge to form a periodic hole array 

    Murray, W. Andrew; Astilean, Simion; Barnes, William L. (American Physical Society, 2004)
    We present results of experiments to determine the dispersion of the plasmon modes associated with periodic silver nanoparticle and nanohole arrays fabricated using an extension of the nanosphere lithography technique. ...
  • Transmission of light through periodic arrays of square holes: From a metallic wire mesh to an array of tiny holes 

    Bravo-Abad, J.; Martin-Moreno, L.; Garcia-Vidal, F. J.; Hendry, Euan; Gómez Rivas, J. (American Physical Society, 2007)
    A complete landscape is presented of the electromagnetic coupling between square holes forming a two-dimensional periodic array in a metallic film. By combining both experimental and theoretical results along with a ...
  • Transmission of microwave radiation through a sub-wavelength slit with internal structure 

    Lockyear, Matthew J.; Hibbins, Alastair P.; Sambles, J. Roy (SPIE, 2008)
    Fabry-Perot cavities are perhaps the best known of the optical transmission resonators, with cavity field enhancement accomplished by two parallel and partially reflecting planes. Recently it has been shown that arrays of ...
  • Transmission of microwaves through a stepped subwavelength slit 

    Lockyear, Matthew J.; Hibbins, Alastair P.; Sambles, J. Roy (American Institute of Physics, 2007)
    The transmission of normally incident plane wave microwaves through a single stepped subwavelength slit in a thick metal plate is explored. The presence of the step substantially increases the radiation wavelength which ...
  • The transverse magnetic reflectivity minimum of metals 

    Hooper, Ian R.; Sambles, J. Roy; Bassom, Andrew P. (Optical Society of America, 2008)
    Metal surfaces, which are generally regarded as excellent reflectors of electromagnetic radiation, may, at high angles of incidence, become strong absorbers for transverse magnetic radiation. This effect, often referred ...
  • Tuneable Fabry–Perot etalon for terahertz radiation 

    Jewell, Sharon A.; Hendry, Euan; Isaac, Thomas Henry; Sambles, J. Roy (Institute of Physics and Deutsche Physikalische Gesellschaft, 2008)
    An indium tin oxide-clad liquid crystal filled Fabry–Perot etalon structure has been shown to act as an effective narrow-band filter at terahertz frequencies. An applied voltage, which controls the alignment of the nematic ...
  • Ultrafast charge generation in a semiconducting polymer studied with THz emission spectroscopy 

    Hendry, Euan; Koeberg, Mattijs; Schins, Juleon M.; Siebbeles, L. D. A.; Bonn, Mischa (American Physical Society, 2004)
    We study the ultrafast charge generation in a semiconducting polymer (MEH-PPV) by measuring the radiated THz field after photoexciting the biased polymer with a femtosecond visible pulse. The subpicosecond temporal ...
  • Ultrafast optical switching of the THz transmission through metallic subwavelength hole arrays 

    Hendry, Euan; Lockyear, Matthew J.; Gómez Rivas, J.; Kuipers, L.; Bonn, Mischa (American Physical Society, 2007)
    We demonstrate ultrafast optical switching of the transmission of terahertz radiation through a metal grating with subwavelength holes. By fabricating the grating on a semiconductor silicon substrate, we are able to control ...
  • Voltage dependent director of a homeotropic negative liquid crystal cell 

    Ruan, Lizhen; Yang, Fuzi; Sambles, J. Roy (American Institute of Physics, 2008)
    Thin layers of obliquely (60° to normal) thermally evaporated SiOx lead to homeotropic alignment of a nematic liquid crystal (LC) having negative dielectric anisotropy. Under application of an ac voltage the director, as ...
  • Waveguide arrays as plasmonic metamaterials: transmission below cutoff 

    Hibbins, Alastair P.; Lockyear, Matthew J.; Hooper, Ian R.; Sambles, J. Roy (American Physical Society, 2006)
    Since the work of Ebbesen et al. [Nature (London) 391, 667 (1998)], there has been immense interest in the optical properties of subwavelength holes in metal layers. While the enhanced transmission observed is generally ...