Yazar "Haglund, Richard F." seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim
    Yayın
    Nonreciprocal switching of VO2 thin films on microstructured surfaces
    (Optical Soc Amer, 2010-05-15) Karakurt, İsmail; Adams, Charles H; Leiderer, Paul; Boneberg, Johannes; Haglund, Richard F.
    We demonstrate that the combination of near-field focusing and a switchable oxide layer permits construction of a modulator with different optical switching thresholds in two opposing directions. For that purpose VO2 layers are deposited onto spherical micrometer-sized particles. The phase transition in VO2 is induced by a nanosecond-pulsed Nd:YAG laser from two different directions. The measured thresholds differ by a factor of 2.4, consistent with calculated differences in the intensities in the two directions.
  • Küçük Resim
    Yayın
    Transmission increase upon switching of VO2 thin films on microstructured surfaces
    (American Institute of Physics, 2007-08-27) Karakurt, İsmail; Boneberg, Johannes; Leiderer, Paul; Lopez, Rene; Halabica, Andrej; Haglund, Richard F.
    The authors compare transmission measurements of near-infrared light through VO2 thin films on smooth substrates and on ordered arrays of silica microspheres. When the samples are heated above the critical temperature for the semiconductor-metallic phase transition, smooth thin films show reduced transmission independent of thickness; however, the VO2 film deposited on the microspheres may show either reduced or enhanced transmission, depending on VO2 film thickness. They show that this at a first glance, unexpected behavior is directly related to the change of scattering efficiency upon the phase transition. This suggests that optical transmission through thin-film microstructures could be tuned by an appropriate combination of microsphere ordering and VO2 film thickness.