GENERAL ENQUIRIES: Tel: + 27 12 841 2911 | Email: callcentre@csir.co.za

Browsing by Author "Forbes, A"

Sort by: Order: Results:

  • Mhlanga, T; Dudley, Angela L; McDonald, A; Roux, FS; Lavery, M; Padgett, M; Forbes, A (SPIE Digital llibrary, 2013-02)
    A procedure to efficiently sort orbital angular momentum (OAM) states of light, by performing a Cartesian to log-polar coordinate transformation which translates helically phased beams into a transverse phase gradient, ...
  • Trichili, A; Dudley, Angela L; Salem, AB; Ndagano, B; Zghal, M; Forbes, A (SPIE, 2015-08)
    The authors experimentally demonstrate an information encoding protocol using the two degrees of freedom of Laguerre Gaussian modes having different radial and azimuthal components. A novel method, based on digital holography, ...
  • Trichili, A; Salem, AB; Dudley, Angela; Zghal, M; Forbes, A (Optical Society of America, 2016-07)
    We experimentally demonstrate an efficient information transmission technique using Laguerre Gaussian (LG) modes. This technique is based on multiplexing and demultiplexing multiple LG modes with different azimuthal and ...
  • Dudley, Angela L; Mafu, M; Goyal, S; Giovannini, D; McLaren, M; Konrad, T; Padgett, MJ; Petruccione, F; Lutkenhaus, N; Forbes, A (2013-07)
    We encode mutually unbiased bases (MUBs) using the higher-dimensional orbital angular momentum (OAM) degree of freedom associated with optical fields. We illustrate how these states are encoded with the use of a spatial ...
  • Zhang, YI; Roux, FS; Konrad, T; Agnew, M; Leach, J; Forbes, A (American Association for the Advancement of Science, 2016-02)
    Many protocols in quantum science, for example, linear optical quantum computing, require access to large-scale entangled quantum states. Such systems can be realized through many-particle qubits, but this approach often ...
  • McLaren, M; Agnew, M; Leach, J; Roux, FS; Padgett, MJ; Boyd, RW; Forbes, A (Optical Society of America, 2012-10)
    Orbital angular momentum (OAM) entanglement is investigated in the Bessel-Gaussian (BG) basis. Having a readily adjustable radial scale, BG modes provide an alternative basis for OAM entanglement over Laguerre-Gaussian ...
  • Dudley, Angela L; Vasilyeu, R; Forbes, A; Khilo, N; Ropot, P (2009-07)
    This presentation provides information on experimental generation and application of the superposition of higher-order Bessel beams. The superposition of zero order Bessel beams can be used to measure the radius of curvature ...
  • Katumba, G; Olumekor, L; Forbes, A; Wackelgard, E (2006-07)
    The investigation and development of carbon-silica composites has been going on for some time. Different applications such as adsorbents, biosensors, templates and solar absorbers have emanated from these studies. The ...
  • Yalisi, B; Katumba, G; Forbes, A; Pillay, SR (2009-06)
    Selective solar absorbers are devices that have been designed to absorb as much as possible of the solar radiation which is in the wavelength range of 0.3 to 2.5 µm and to minimise thermal emittance in the wavelength range ...
  • Masina, BN; Lafane, S; Wu, L; Kerdja, T; Abdelli-Messaci, S; Forbes, A (2013-10)
    The main objective of this study is to fully optimise the synthesis of vanadium oxide nanostructures using pulsed laser deposition. We will attempt to realise this by studying the mechanism of the plasma formation and ...
  • Nkosi, SS; Gavi, HM; Motaung, DE; Keartland, J; Sideras-Haddad, E; Forbes, A; Mwakikunga, BW (Hindawi Publishing Corporation, 2013)
    Electron spin resonance (ESR) measurements at room temperature and X-band microwave frequency were performed on highly crystalline FePt system thin films. Fairly high DC static magnetic field absorption of about 300 mT was ...
  • Govender, M; Shikwambana, L; Mwakikunga, BW; Sideras-Haddad, E; Erasmus, RM; Forbes, A (Springer, 2010-06)
    This report focuses on the production of multi-phase WO3 and WO3-x (where x could vary between 0.2 and 0.33) nanostructures synthesized by CO2-laser pyrolysis technique at varying laser wavelengths (9.22-10.82 mm) and power ...
  • Gailele, Lucas M; Dudley, Angela; Ndagano, B; McLaren M, M; Rosales, C; Forbes, A (2016-07)
    The orbital angular momentum (OAM) of light has become the focus of intensive research. Traditional optical communication systems optimize multiplexing in the polarization and the wavelength of light to attain an increase ...
  • Dudley, Angela L; Forbes, A (Optical Society of America, 2012-04)
    In this work we use a phase-only spatial light modulator (SLM) to mimic a ring-slit aperture, containing multiple azimuthally varying phases at different radial positions. The optical Fourier transform of such an aperture ...
  • Mafusire, C; Forbes, A; Snedden, Glen C; Mahlase, ACK; Michaelis, MM; Mathuthu, M (2006-07)
    When a heated pipe is rotated, the dynamics of the gas inside exhibit properties reminiscent of a solid-state positive lens. The properties are a result of a parabolic distribution of refractive index in the pipe which is ...
  • Litvin, IA; Forbes, A (Optical Society of America, 2009-10)
    The authors outline a resonator design that allows for the selection of a Gaussian mode by diffractive optical elements. This is made possible by the metamorphosis of a Gaussian beam into a flat-top beam during propagation ...
  • Mafusire, C; Forbes, A (Optical Society of America, 2011-07)
    The authors outline a theory for the calculation of the beam quality factor of an aberrated laser beam. They provide closed form equations that show that the beam quality factor of an aberrated Gaussian beam depends on all ...
  • Li, Y; Dudley, Angela L; Mhlanga, T; Escutia, MJ; Forbes, A (SPIE Proceedings, 2013-08)
    We experimentally generate non-diffracting vector vortex beams by using a Spatial Light Modulator (SLM) and an azimuthal birefringent plate (q-plate). The SLM generates scalar Bessel beams and the q-plate converts them to ...
  • Dudley, Angela L; Lib, Y; Mhlanga, T; Escuti, M; Forbes, A (SPIE Proceedings, 2014-03)
    We demonstrate how to create non-diffracting vector Bessel beams by implementing a spatial light modulator (SLM) to generate scalar Bessel beams which are then converted into vector fields by the use of an azimuthally-varying ...
  • Dudley, Angela L; Li, Y; Mhlanga, T; Escuti, M; Forbes, A (Optical Society of America, 2013-09)
    Nondiffracting vector Bessel beams are of considerable interest due to their nondiffracting nature and unique high-numerical-aperture focusing properties. Here we demonstrate their creation by a simple procedure requiring ...