Now showing items 821-840 of 851

  • 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 demagnetization of Co 25Ni 75/Pt multilayers with perpendicular anisotropy at elevated temperatures 

    Wilks, R.; Hicken, R.J.; Ali, M.; Hickey, B.J. (American Institute of Physics, 2005)
    Ultrafast demagnetization has been studied in Si/Pt(160 Å)/[Co25Ni75(x)/Pt(8 Å)]20 (x = 3, 4.5, and 6 Å) multilayers with perpendicular anisotropy by magneto-optical pump-probe measurements in the polar geometry. Time-resolved ...
  • Ultrafast magnetization dynamics of spintronic nanostructures 

    Keatley, Paul Steven; Kruglyak, V.V.; Gangmei, Prim; Hicken, R.J. (Royal Society, 2011)
    The ultrafast (sub-nanosecond) magnetization dynamics of ferromagnetic thin films and elements that find application in spintronic devices is reviewed. The major advances in the understanding of magnetization dynamics in ...
  • Ultrafast optical modification of exchange interactions in iron oxides 

    Mikhaylovskiy, Rostislav; Hendry, Euan; Secchi, A.; Mentink, J.H.; Eckstein, M.; Wu, A.; Pisarev, R.V.; Kruglyak, V.V.; Katsnelson, M.I.; Rasing, T.; Kimel, A.V. (Nature Publishing Group, 2015-09-16)
    Ultrafast non-thermal manipulation of magnetization by light relies on either indirect coupling of the electric field component of the light with spins via spin-orbit interaction or direct coupling between the magnetic ...
  • Ultrafast optical modification of magnetic anisotropy and stimulated precession in an epitaxial Co2 MnAl thin film 

    Liu, Y.; Shelford, L.R.; Kruglyak, V.V.; Hicken, R.J.; Sakuraba, Y.; Oogane, M.; Ando, Y.; Miyazaki, T. (American Institute of Physics, 2007)
    An all-optical pump-probe method was used to study magnetization precession in an epitaxial Co2MnAl Heusler alloy thin film. The frequency and amplitude of precession showed a clear fourfold variation as the orientation ...
  • Ultrafast optical parametric pumping of magnetization reorientation and precessional dynamics in DyFe2/YFe2 exchange springs. 

    Shelford, LR; Liu, Y; Al-Jarah, U; de Groot, PA; Bowden, GJ; Ward, RC; Hicken, RJ (American Physical Society, 2014-08-08)
    The magnetization dynamics of a wound [DyFe(2)(20  Å)/YFe(2)(80  Å)](×40) exchange spring multilayer have been explored in optical pump probe experiments. Ultrafast optical heating was used to modify the magnetic parameters ...
  • 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 ...
  • Ultrasensitive detection and characterization of biomolecules using superchiral fields 

    Hendry, Euan; Carpy, T.; Johnston, J.; Popland, M.; Mikhaylovskiy, Rostislav; Lapthorn, A.J.; Kelly, S.M.; Barron, L.D.; Gadegaard, N.; Kadodwala, M. (Nature Publishing Group, 2010)
    The spectroscopic analysis of large biomolecules is important in applications such as biomedical diagnostics and pathogen detection, and spectroscopic techniques can detect such molecules at the nanogram level or lower. ...
  • Ultrathin Quadrifilar Spirals and Spiral Ensembles 

    Meinzer, Nina; Sambles, J. Roy; Hibbins, Alastair P. (-, 2015-09)
    We investigate the eigenmodes of both ultrathin quadrifilar spirals and ensembles made up of such spirals by comparing experimental near-field scans with numerical finite-element models. These modes can be understood in ...
  • Unforeseen high temperature and humidity stability of FeCl3 intercalated few layer graphene 

    Wehenkel, DJ; Bointon, TH; Booth, T; Bøggild, P; Craciun, MF; Russo, S (Nature Publishing Group, 2015)
    We present the first systematic study of the stability of the structure and electrical properties of FeCl3 intercalated few-layer graphene to high levels of humidity and high temperature. Complementary experimental techniques ...
  • A unique self-organization of bacterial sub-communities creates iridescence in Cellulophaga lytica colony biofilms. 

    Kientz, B; Luke, S; Vukusic, P; Péteri, R; Beaudry, C; Renault, T; Simon, D; Mignot, T; Rosenfeld, E (Nature Publishing Group: Open Access Journals - Option C, 2016-01-28)
    Iridescent color appearances are widespread in nature. They arise from the interaction of light with micron- and submicron-sized physical structures spatially arranged with periodic geometry and are usually associated with ...
  • An update of the UK’s Design Summer Years Probabilistic Design Summer Years for Enhanced Overheating Risk Analysis in Building Design 

    Eames, Matthew E. (Sage Publications, 2016)
    Overheating is increasingly becoming a key issue for building design across the world. In the UK better building fabric performance and warmer weather can increase the risk of overheating events in badly designed buildings. ...
  • An update: improvements in imaging perfluorocarbon-mounted plant leaves with implications for studies of plant pathology, physiology, development and cell biology 

    Littlejohn, GR; Mansfield, JC; Christmas, JT; Witterick, E; Fricker, MD; Grant, MR; Smirnoff, N; Everson, RM; Moger, J; Love, J (Frontiers Media, 2014-04-23)
    Plant leaves are optically complex, which makes them difficult to image by light microscopy. Careful sample preparation is therefore required to enable researchers to maximize the information gained from advances in ...
  • The upper atmosphere of the exoplanet HD 209458 b revealed by the sodium D lines. Temperature-pressure profile, ionization layer, and thermosphere 

    Vidal-Madjar, A.; Sing, David K.; Lecavelier des Etangs, A.; Ferlet, R.; Desert, J.-M.; Hebrard, G.; Boisse, I.; Ehrenreich, D.; Moutou, C. (EDP Sciences for European Southern Observatory (ESO), 2011)
    A complete reassessment of the Hubble Space Telescope (HST) observations of the transits of the extrasolar planet HD 209458 b has provided a transmission spectrum of the atmosphere over a wide range of wavelengths. Analysis ...
  • Urban form and function as building performance parameters 

    Futcher, Julie Ann; Kershaw, Tristan; Mills, Gerald (Elsevier, 2013)
    The climate in cities differs significantly from those found in the surrounding area. These differences results from modifications of the Earth's surface that alters the disposition of “natural energy balance” at a micro-scale ...
  • Use of microscale coplanar striplines with indium tin oxide windows in optical ferromagnetic resonance measurements 

    Keatley, Paul Steven; Kruglyak, V.V.; Barman, A.; Ladak, S.; Hicken, R.J.; Scott, J.; Rahman, M. (American Institute of Physics, 2005)
    It is shown that a coplanar stripline structure containing indium tin oxide windows can be used to perform optical ferromagnetic resonance measurements on a sample grown on an opaque substrate, using a pulsed magnetic field ...
  • Use of the Faraday optical transformer for ultrafast magnetization reversal of nanomagnets 

    Kruglyak, V.V.; Portnoi, M.E.; Hicken, R.J. (SPIE - Society of Photo-Optical Instrumentation Engineers, 2007)
    We propose a new strategy for ultrafast magnetization reversal of nanomagnets. Due to the Inverse Faraday Effect, circularly polarized optical pulses induce a pulsed magnetic flux in materials with large magneto-optical ...
  • Using the UM dynamical cores to reproduce idealised 3-D flows 

    Mayne, NJ; Baraffe, I; Acreman, DM; Smith, C; Wood, N; Amundsen, DS; Thuburn, J; Jackson, DR (European Geosciences Union (EGU), 2014-12-18)
    We demonstrate that both the current (New Dynamics), and next generation (ENDGame) dynamical cores of the UK Met Office global circulation model, the UM, reproduce consistently, the long-term, large-scale flows found in ...
  • The UV-Excess survey of the northern Galactic plane 

    Groot, Paul J.; Verbeek, Kars; Greimel, Robert; Irwin, Mike; González-Solares, Eduardo; Gänsicke, Boris T.; de Groot, Eelco; Drew, Janet; Augusteijn, Thomas; Aungwerojwit, Amornrat; Barlow, Mike; Barros, Susana; Van Den Besselaar, Else J. M.; Casares, Jorge; Corradi, Romano; Corral-Santana, Jesús M.; Deacon, Niall; van Ham, Wilbert; Hu, Haili; Heber, Uli; Jonker, Peter G.; King, Rob; Knigge, Christian; Mampaso, Antonio; Marsh, Tom R.; Morales-Rueda, Luisa; Napiwotzki, Ralf; Naylor, Tim; Nelemans, Gijs; Oosting, Tim; Pyrzas, Stylianos; Pretorius, Magaretha; Rodríguez-Gil, Pablo; Roelofs, Gijs H. A.; Sale, Stuart; Schellart, Pim; Steeghs, Danny; Szyszka, Cezary; Unruh, Yvonne; Walton, Nicholas A.; Weston, Simon; Witham, Andrew; Woudt, Patrick; Zijlstra, Albert (Oxford University Press for Royal Astronomical Society, 2009)
    The UV-Excess survey of the northern Galactic plane images a 10° × 185° wide band, centred on the Galactic equator using the 2.5-m Isaac Newton Telescope in four bands (I5875) down to ~21-22 mag ( in I5875). The setup and ...
  • V346 Normae: First post-outburst observations of an FU Orionis star 

    Kraus, S; A. Caratti o Garatti; R. Garcia-Lopez; A. Kreplin; A. Aarnio; J.D. Monnier; T. Naylor; G. Weigelt (Oxford University Press (OUP) on behalf of the Royal Astronomical Society, 2016)
    During their formation phase stars gain most of their mass in violent episodic accretion events, such as observed in FUOrionis (FUor) and EXor stars. V346Normae is a well-studied FUor that underwent a strong outburst ...