Imaging of electric and magnetic fields near plasmonic nanowires Journal Article

Author(s): Kabakova, Irina V; De Hoogh, Anouk; Van Der Wel, Ruben E C; Wulf, Matthias; Le Feber, Boris; Kuipers, Laurens K
Article Title: Imaging of electric and magnetic fields near plasmonic nanowires
Affiliation IST Austria
Abstract: Near-field imaging is a powerful tool to investigate the complex structure of light at the nanoscale. Recent advances in near-field imaging have indicated the possibility for the complete reconstruction of both electric and magnetic components of the evanescent field. Here we study the electro-magnetic field structure of surface plasmon polariton waves propagating along subwavelength gold nanowires by performing phase- and polarization-resolved near-field microscopy in collection mode. By applying the optical reciprocity theorem, we describe the signal collected by the probe as an overlap integral of the nanowire's evanescent field and the probe's response function. As a result, we find that the probe's sensitivity to the magnetic field is approximately equal to its sensitivity to the electric field. Through rigorous modeling of the nanowire mode as well as the aperture probe response function, we obtain a good agreement between experimentally measured signals and a numerical model. Our findings provide a better understanding of aperture-based near-field imaging of the nanoscopic plasmonic and photonic structures and are helpful for the interpretation of future near-field experiments.
Journal Title: Scientific Reports
Volume: 6
ISSN: 20452322
Publisher: Nature Publishing Group  
Date Published: 2016-03-07
Start Page: Article number: 22665
Copyright Statement: CC BY 4.0
DOI: 10.1038/srep22665
Notes: This work is supported part of the research program of the Netherlands Foundation for Fundamental Research on Matter (FOM) and the Netherlands Organization for Scientific Research (NWO), and part of this work has been funded by the project ‘SPANGL4Q’, which acknowledges the financial support of the Future and Emerging Technologies (FET) program within the Seventh Framework Programme for Research of the European Commission, under FETOpen grant number: FP7-284743. L.K. acknowledges funding from ERC Advanced, Investigator Grant (no. 240438-CONSTANS).
Open access: yes (OA journal)
IST Austria Authors
  1. Matthias Wulf
    2 Wulf