TY  - JOUR
A1  - Walla, Frederik William
A1  - Wiecha, Matthias
A1  - Mecklenbeck, Nicolas
A1  - Beldi, Sabri
A1  - Keilmann, Fritz
A1  - Thomson, Mark David
A1  - Roskos, Hartmut
T1  - Anisotropic excitation of surface plasmon polaritons on a metal film by a scattering-type scanning near-field microscope with a non-rotationally-symmetric probe tip
T2  - Nanophotonics
N2  - We investigated the excitation of surface plasmon polaritons on gold films with the metallized probe tip of a scattering-type scanning near-field optical microscope (s-SNOM). The emission of the polaritons from the tip, illuminated by near-infrared laser radiation, was found to be anisotropic and not circularly symmetric as expected on the basis of literature data. We furthermore identified an additional excitation channel via light that was reflected off the tip and excited the plasmon polaritons at the edge of the metal film. Our results, while obtained for a non-rotationally-symmetric type of probe tip and thus specific for this situation, indicate that when an s-SNOM is employed for the investigation of plasmonic structures, the unintentional excitation of surface waves and anisotropic surface wave propagation must be considered in order to correctly interpret the signatures of plasmon polariton generation and propagation.
KW  - surface plasmon polaritons
KW  - surface waves
KW  - near-field microscopy
KW  - s-SNOM
Y1  - 2017
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/75517
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-755175
VL  - 7.2018
IS  - 1
SP  - 269
EP  - 276
PB  - de Gruyter
CY  - Berlin
ER  -