Optical near-field studies of waveguiding organic nanofibers by angular dependent excitation. Authors: Christian Maibohm¹, Tomasz Kawalec¹, Vladimir G. Bordo² and Horst-Günter Rubahn¹. Institutions: 1) NanoSYD, MCI, University of southern Denmark, DK- 6400 Sønderborg Denmark . 2) Institute of General Physics, Russian Academy of Science, 119991 Moscow, Russia. Abstract: Single crystalline organic nanofibers of para-phenylene are grown in UHV by MBE and dipole assisted self-assembly. In the optical far-field the fluorescence from a single nanofiber is spectrally well defined and highly polarized. By UV excitation in a fluorescence microscope it has also been shown that nanofibers have waveguiding properties. To further characterize the waveguiding properties the optical near-field has to be investigated. This is done by transferring nanofibers to an quartz half sphere where they are excited by the evanescent wave from a total internal reflected UV laser. The optical near-field is probed by the fiber tip of a SNOM (scanning near-field optical microscope). In the setup it is possible to change the angle of incidence of the excitation laser i.e. change the k-vector of the evanescent wave in order to see the change in the coupling to guided modes in the nanofiber.
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10-th scool-conference Advanced materials and technologies and 3rd summer scool European doctorate in physics and chemistry of advanced materials, 2008