Regensburg 2010 – wissenschaftliches Programm
DS 27.5: Vortrag
Mittwoch, 24. März 2010, 11:30–11:45, H32
Swichable Hot Spots in Bipyramid-Nanoresonators — •Siji Wu, Calin Hrelescu, Frank Jäckel, and Jochen Feldmann — Photonics and Optoelectronics Group, Department of Physics and Center for Nano Science (CeNS), Ludwig-Maximilians-Universität München, Amalienstrasse 54, 80799 München, Germany
Highly enhanced and strongly localized electromagnetic fields, so-called hot spots, are attractive for imaging applications, based on raman scattering or fluorescence enhancement.[1,2] Hot spots can be provided by nonspherical gold nanoparticles or nanoparticles aggregates. Here, we report on nanoresonators consisting of two bipyramidal gold nanoparticles prepared by AFM manipulation. Applying a force with the AFM allows switching between the two possible adsorption geometries of an individual bipyramid on the substrate. The plasmonic coupling between two bipyramids is different in the two configurations. Consequently, the hot spot in the nanoresonator can be switched mechanically. Furthermore, the hot spot can be located within 1nm above the substrate surface in contrast to dimer nanoresonators from spheres, rods or ellipsoids.
 C. Hrelescu, T.K. Sau, A.L. Rogach, F. Jäckel, J. Feldmann Appl. Phys. Lett., 94, 153113 (2009)
 A. Bek, R. Jansen, M. Ringler, S. Mayilo, T. A. Klar, J. Feldmann Nano Lett., 8 (2), 485 (2008)