Your browser doesn't support javascript.
loading
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures.
Kataja, Mikko; Cichelero, Rafael; Herranz, Gervasi.
Affiliation
  • Kataja M; Institut de Ciència de Materials de Barcelona.
  • Cichelero R; Institut de Ciència de Materials de Barcelona; Department of Physics, University of Gothenburg.
  • Herranz G; Institut de Ciència de Materials de Barcelona; gherranz@icmab.es.
J Vis Exp ; (153)2019 11 21.
Article in En | MEDLINE | ID: mdl-31814609
ABSTRACT
Photonic crystals are periodic nanostructures that can support a variety of confined electromagnetic modes. Such confined modes are usually accompanied by local enhancement of electric field intensity that strengthens light-matter interactions, enabling applications such as surface-enhanced Raman scattering (SERS) and surface plasmon enhanced sensing. In the presence of magneto-optically active materials, the local field enhancement gives rise to anomalous magneto-optical activity. Typically, the confined modes of a given photonic crystal depend strongly on the wavelength and incidence angle of the incident electromagnetic radiation. Thus, spectral and angular-resolved measurements are needed to fully identify them as well as to establish their relationship with the magneto-optical activity of the crystal. In this article, we describe how to use a Fourier-plane (back focal plane) microscope to characterize magneto-optically active samples. As a model system, here we use a plasmonic grating built out of magneto-optically active Au/Co/Au multilayer. In the experiments, we apply a magnetic field on the grating in situ and measure its reciprocal space response, obtaining the magneto-optical response of the grating over a range of wavelengths and incident angles. This information enables us to build a complete map of the plasmonic band structure of the grating and the angle and wavelength dependent magneto-optical activity. These two images allow us to pinpoint the effect that the plasmon resonances have on the magneto-optical response of the grating. The relatively small magnitude of magneto-optical effects requires a careful treatment of the acquired optical signals. To this end, an image processing protocol for obtaining magneto-optical response from the acquired raw data is laid out.
Subject(s)

Full text: 1 Collection: 01-internacional Database: MEDLINE Main subject: Nanostructures Type of study: Guideline Language: En Journal: J Vis Exp Year: 2019 Document type: Article

Full text: 1 Collection: 01-internacional Database: MEDLINE Main subject: Nanostructures Type of study: Guideline Language: En Journal: J Vis Exp Year: 2019 Document type: Article