Light-enhanced diffusion at the solid-liquid interface

ORAL

Abstract

Positively-charged rhodamine 6G molecules were allowed to adsorb onto quartz and mica surfaces and their translational and rotational diffusion was studied simultaneously by combined fluorescence correlation spectroscopy and time-correlated single photon counting. Surprisingly, the surface translational diffusion coefficient increased in direct proportion to the laser power used to excite these dye molecules. To elucidate the diffusion mechanism, we have investigated the excitation wavelength dependence, the spatial position dependence of diffusion coefficients, and the correlations between rotation and translation motion.

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Authors

  • Sung Chul Bae

    Department of Materials Science and Engineering, University of Illinois, Materials Science and Engineering, University of Illinois

  • Janet Wong

    Department of Materials Science and Engineering, University of Illinois, Dept. Materials Science and Engineering, University of Illinois at Urbana-Champaign

  • Steve Granick

    Department of Materials Science and Engineering, University of Illinois, University of Illinois, Urbana-Champaign, material science and engineering, UIUC, Materials Science and Engineering, University of Illinois, Dept of Materials Science \& Engineering, University of Illinois at Urbana-Champaign, Dept. Materials Science and Engineering, University of Illinois at Urbana-Champaign, University of Illinois at Urbana-Champaign, University of Illinois, Dept of Materials Science \& Engineering, Univ of Illinois at Urbana-Champaign, Material Science and Engineering, UIUC