Now showing items 184-203 of 479

  • Imaging collective magnonic modes in 2D arrays of magnetic nanoelements 

    Kruglyak, V.V.; Keatley, Paul Steven; Neudert, A.; Hicken, R.J.; Childress, J.R.; Katine, J.A. (American Physical Society, 2010)
    We have used time resolved scanning Kerr microscopy to image collective spin wave modes within a 2D array of magnetic nanoelements. Long wavelength spin waves are confined within the array as if it was a continuous element ...
  • Imaging small-amplitude magnetization dynamics in a longitudinally magnetized microwire 

    Kruglyak, V.V.; Keatley, Paul Steven; Neudert, A.; Delchini, M.; Hicken, R.J.; Childress, J.R.; Katine, J.A. (American Physical Society, 2008)
    We have used time-resolved scanning Kerr microscopy to study spin waves in a magnetic microwire subjected to a bias magnetic field applied parallel to its long axis. The spin-wave spectra obtained from different points ...
  • Imaging the dephasing of spin wave modes in a square thin film magnetic element 

    Barman, A.; Kruglyak, V.V.; Hicken, R.J.; Rowe, J.M.; Kundrotaite, A.; Scott, J.; Rahman, M. (American Physical Society, 2004)
    We have used time-resolved scanning Kerr effect microscopy to study dephasing of spin wave modes in a square Ni81Fe19 element of 10 μm width and 150 nm thickness. When a static magnetic field H was applied parallel to an ...
  • Imaging the uptake of gold nanoshells in live cells using plasmon resonance enhanced four wave mixing microscopy 

    Garrett, Natalie; Whiteman, Matt; Moger, Julian (Optical Society of America, 2011)
    Gold nanoshells (GNS) are novel metal nanoparticles exhibiting attractive optical properties which make them highly suitable for biophotonics applications. We present a novel investigation using plasmon-enhanced four wave ...
  • Importance of diffraction in determining the dispersion of designer surface plasmons 

    Hendry, Euan; Hibbins, Alastair P.; Sambles, J. Roy (American Physical Society, 2008)
    By employing a modified modal matching approach, we obtain explicit analytical expressions relating frequency to in-plane wave vector for the surface electromagnetic mode confined at the interface between vacuum and a ...
  • The importance of radiative feedback for the stellar initial mass function 

    Bate, Matthew R. (Oxford University Press / Royal Astronomical Society, 2009)
    We investigate the effect of radiative feedback on the star formation process using radiation hydrodynamical simulations. We repeat the previous hydrodynamical star cluster formation simulations of Bate et al. and Bate & ...
  • Independently controlling permittivity and diamagnetism in broadband, low-loss, isotropic metamaterials at microwave frequencies 

    Parke, L.; Hooper, Ian R.; Edwards, E.; Cole, N.; Youngs, I.J.; Hibbins, Alastair P.; Sambles, J. Roy (American Institute of Physics (AIP), 2015-03-09)
    A metamaterial based on the design of Shin et al. [Phys. Rev. Lett. 102, 093903 (2009)] that allows independent control of its permeability and permittivity has been fabricated and experimentally characterised. It is ...
  • Induced currents in the quantum Hall regime: energy storage, persistence, and I-V characteristics 

    Smith, Martin J.; Usher, Charles D.H.; Williams, Charles D.H.; Shytov, A.V.; Sachrajda, A.S.; Kam, A.; Wasilewski, Z.R. (American Physical Society, 2012)
    Induced currents associated with the quantum Hall effect are studied in the temperature range 39 mK to 1.6 K, and at Landau-level filling factors ν=1,2,3,4, and 6, using torsion-balance magnetometry. A quantitative link ...
  • Induced currents, frozen charges and the quantum Hall effect breakdown 

    Kavokin, K.V.; Portnoi, M.E.; Matthews, A.J.; Usher, Alan; Gething, J.; Ritchie, D.A.; Simmons, M.Y. (Elsevier, 2005)
    Puzzling results obtained from torque magnetometry in the quantum Hall effect regime are presented, and a theory is proposed for their explanation. Magnetic moment saturation, which is usually attributed to the quantum ...
  • Inefficient star formation: The combined effects of magnetic fields and radiative feedback 

    Price, Daniel J.; Bate, Matthew R. (Oxford University Press / Royal Astronomical Society, 2009)
    We investigate the effects of magnetic fields and radiative protostellar feedback on the star formation process using self-gravitating radiation magnetohydrodynamical calculations. We present results from a series of ...
  • Interchain effects in the ultrafast photophysics of a semiconducting polymer: THz time-domain spectroscopy of thin films and isolated chains in solution 

    Hendry, Euan; Koeberg, Mattijs; Schins, Juleon M.; Nienhuys, H. K.; Sundström, V.; Siebbeles, L. D. A.; Bonn, Mischa (American Physical Society, 2005)
    We compare the generation and decay dynamics of charges and excitons in a model polymer semiconductor (MEH-PPV) in solution and drop-cast thin films, by recording the sub-ps transient complex conductivity using THz time-domain ...
  • Interfacial structure and half-metallic ferromagnetism in Co2MnSi-based magnetic tunnel junctions 

    Telling, N.D.; Keatley, Paul Steven; van der Laan, Gerrit; Hicken, R.J.; Arenholz, E.; Sakuraba, Y.; Oogane, M.; Ando, Y.; Miyazaki, T. (American Physical Society, 2006)
    X-ray absorption (XAS) and x-ray magnetic circular dichroism (XMCD) techniques are utilized to explore the ferromagnetic/barrier interface in Co2MnSi full Heusler alloy magnetic tunnel junctions. Structural and magnetic ...
  • Investigating the productivity of office workers to quantify the effectiveness of climate change adaptation measures 

    Kershaw, Tristan; Lash, Daniel (Elsevier, 2013)
    The impacts of climate change pose many threats to our current way of life. However, the current mitigation agenda has not yet produced the carbon emission reductions needed implying that some level of adaptation will be ...
  • Investigation of the rise time and damping of spin excitations in Ni81Fe19 thin films 

    Wu, J.; Hughes, N.D.; Moore, J.R.; Hicken, R.J. (American Institute of Physics, 2001)
    The rise and damping of spin excitations in three Ni81Fe19 films of thickness 50, 500, and 5000 Å have been studied with an optical pump–probe technique in which the sample is pumped with an optically triggered magnetic ...
  • Investigation of ultrafast demagnetization and cubic optical nonlinearity of Ni in the polar geometry 

    Wilks, R.; Hicken, R.J.; Ali, M.; Hickey, B.J.; Buchanan, J.D.R.; Pym, A.T.G.; Tanner, B.K. (American Institute of Physics, 2004)
    Femtosecond optical pump-probe experiments were performed upon a Ni(720 Å)/Si(100) sample in the polar geometry with the pump beam close to normal incidence. A signal due to the ultrafast demagnetization effect was observed ...
  • Investigation of ultrafast spin dynamics in a Ni thin film 

    Wilks, R.; Hughes, N.D.; Hicken, R.J. (American Institute of Physics, 2002)
    Optically induced ultrafast demagnetization has been studied in a polycrystalline nickel thin film by means of a magneto-optical pump-probe technique. The time and magnetic field dependence of the effect have been explored ...
  • Ionization degree of the electron-hole plasma in semiconductor quantum wells 

    Portnoi, M.E.; Galbraith, I. (American Physical Society, 1999)
    The degree of ionization of a nondegenerate two-dimensional electron-hole plasma is calculated using the modified law of mass action, which takes into account all bound and unbound states in a screened Coulomb potential. ...
  • The JCMT gould belt survey: Evidence for radiative heating in serpens MWC 297 and its influence on local star formation 

    Rumble, D.; Hatchell, Jennifer; Gutermuth, R.A.; Kirk, H.; Buckle, J.; Beaulieu, S.F.; Berry, D.S.; Broekhoven-Fiene, H.; Currie, M.J.; Fich, M.; Jenness, T.; Johnstone, D.; Mottram, J.C.; Nutter, D.; Pattle, K.; Pineda, J.E.; Quinn, C.; Salji, C.; Tisi, S.; Walker-Smith, S.; Di Francesco, J.; Hogerheijde, M.R.; Ward-Thompson, D.; Allen, L.E.; Cieza, L.A.; Dunham, M.M.; Harvey, P.M.; Stapelfeldt, K.R.; Bastien, P.; Butner, H.; Chen, M.; Chrysostomou, A.; Coude, S.; Davis, C.J.; Drabek-Maunder, Emily R.; Duarte-Cabral, A.; Fiege, J.; Friberg, P.; Friesen, R.; Fuller, G.A.; Graves, S.; Greaves, J.; Gregson, J.; Holland, W.; Joncas, G.; Kirk, J.M.; Knee, L.B.G.; Mairs, S.; Marsh, K.; Matthews, B.C.; Moriarty-Schieven, G.; Rawlings, J.; Richer, J.; Robertson, D.; Rosolowsky, E.; Sadavoy, S.I.; Thomas, H.; Tothill, N.; Viti, S.; White, G.J.; Wilson, C.D.; Wouterloot, J.; Yates, J.; Zhu, Ming (Oxford University Press for Royal Astronomical Society, 2015-02-14)
    We present SCUBA-2 450 and 850 μm observations of the Serpens MWC 297 region, part of the James Clerk Maxwell Telescope (JCMT) Gould Belt Survey of nearby star-forming regions. Simulations suggest that radiative feedback ...
  • The JCMT Gould Belt Survey: SCUBA-2 observations of radiative feedback in NGC1333 

    Hatchell, Jennifer; Wilson, T.; Drabek, E.; Curtis, E.; Richer, J.; Di Francesco, J.; Ward-Thompson, D. (Oxford University Press for Royal Astronomical Society, 2013)
    We present observations of NGC 1333 from SCUBA-2 on the James Clerk Maxwell Telescope (JCMT), observed as a JCMT Gould Belt Survey pilot project during the shared risk campaign when the first of four arrays was installed ...
  • Klein backscattering and Fabry-Pérot interference in graphene heterojunctions 

    Shytov, A.V.; Rudner, M.S.; Levitov, L.S. (American Physical Society, 2008)
    We present a theory of quantum-coherent transport through a lateral p-n-p structure in graphene, which fully accounts for the interference of forward and backward scattering on the p-n interfaces. The backreflection amplitude ...