Photoresponsive polymers for topographic simulation of the optical near-field of a nanometer sized gold tip in a highly focused laser beam.
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.
Gilbert
Yann
Y
Bachelot
Renaud
R
Vial
Alexandre
A
Lerondel
Gilles
G
Royer
Pascal
P
Bouhelier
Alexandre
A
Wiederrecht
Gary
G