title: Photoresponsive polymers for topographic simulation of the optical near-field of a nanometer sized gold tip in a highly focused laser beam.
abstract: The local perturbation of a diffraction-limited spot by a nanometer sized gold tip in a popular apertureless scanning near-field optical microscopy (ASNOM) configuration is reproduced through topography changes in a photoresponsive polymer. Our method relies on the observation of the photochemical migration of azobenzene molecules grafted to a polymer placed beneath the tip. A local molecular displacement has been shown to be activated by a gold tip as a consequence of the lateral surface charge density present at the edges of the tip's end, resulting from a strong near-field depolarization predicted by theory.
authors.forename: Yann
authors.initials: Y
authors.lastname: Gilbert
authors.forename: Renaud
authors.initials: R
authors.lastname: Bachelot
authors.forename: Alexandre
authors.initials: A
authors.lastname: Vial
authors.forename: Gilles
authors.initials: G
authors.lastname: Lerondel
authors.forename: Pascal
authors.initials: P
authors.lastname: Royer
authors.forename: Alexandre
authors.initials: A
authors.lastname: Bouhelier
authors.forename: Gary
authors.initials: G
authors.lastname: Wiederrecht