Bloch-Surface-Waves-Induced Fano Resonance in Magneto-Optical Response of Magnetophotonic Crystals I.V. Soboleva, M.N. Romodina, K.A. Korzun, A.I. Musorin, and A.A. Fedyanin Faculty of Physics, Lomonosov Moscow State University, Moscow 119991, Russia ABSTRACT Magnetophotonic crystals (MPCs) support Bloch surface waves (BSWs) and waveguided modes (WGMs) prop- agation. The influence of the BSW on the Faraday effect in the one-dimensional MPCs is studied. The tech- nique of measuring the angle of Faraday rotation in the MPCs in attenuated total internal reflection scheme in Kretschmann configuration is discussed. The spectra of Faraday rotation demonstrate a Fano-shaped resonance near the spectral-angular position of the BSW resonance both for s- and p-polarized incident light. The presence of the feature in the spectrum of p-polarized light can be explained by the Faraday rotation effect and subsequent BSW excitation mutually enhancing each other. Keywords: Faraday effect, surface electromagnetic waves, magnetophotonic crystals, Kretschmann configura- tion 1. INTRODUCTION In recent decades nanophotonics has focused on the search of the effective ways to control the light on the microscale. The ability of magneto-optical effects to control the polarization of the light beam led to a renewal of interest in them. For example, recently it was shown that the magneto-optical effects such as Faraday and Kerr effects can be used to achieve the polarization shaping of ultrashort laser pulse. 1 Ultrashort pulse shaping is required in the coherent control of quantum states, 2–4 plasma dynamics 5 and other important applications. 6–8 The Faraday effect is governed by a spin-orbit interaction and manifests itself as a rotation of the polarization plane of linearly polarized light passing through the magnetic material. The angle of rotation is determined by the velocity disparity between the left and right circularly polarized waves and the light optical path length in the magnetic medium. In nanostructures with narrow resonances in the reflectance spectra, for example, magnetophotonic crystals, 9–11 microcavities 12–15 or magnetoplasmonic gratings, 16, 17 the Faraday effect can be significantly enhanced due to the phase shifts across the resonance. 18 This work is devoted to the influence of Bloch surface waves in one-dimensional magnetophotonic crystals (MPCs) on the spectral dependence of the Faraday rotation angle. The MPCs are the microstructures consisting of layers of magnetic and non-magnetic materials 19 where the excitation of surface states has recently been shown. 20 Bloch surface waves (BSWs) are excited at the interface of two dielectrics, 21, 22 in this case, the MPC and air, and have an extremely high mean free path and very low spectral and angular width of the resonance. 23, 24 The dispersion relation of the BSWs in photonic crystals lie behind the light line and their excitation requires special excitation schemes. 25 Attenuated total internal reflection schemes in Otto and Kretschmann-Raether geometries are effective, however, the magneto-optical measurement technique requires the due regard of the prism. 26 This paper describes the correct algorithm to measure the Faraday effect near resonance of BSW excited in the MPC with the attenuated total internal reflection scheme in the Kretschmann geometry. The Faraday- rotation-angle spectra are experimentally obtained in the MPC simultaneously with the BSW excitation. The results are discussed taking into account the numerical and experimental reflectance spectra of magnetophotonic crystal. I.V.Soboleva also at: Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow 119071, Russia Contact authors through the Lab website http://nanolab.phys.msu.ru Photonic and Phononic Properties of Engineered Nanostructures VII, edited by Ali Adibi, Shawn-Yu Lin, Axel Scherer, Proc. of SPIE Vol. 10112, 1011210 · © 2017 SPIE CCC code: 0277-786X/17/$18 · doi: 10.1117/12.2252852 Proc. of SPIE Vol. 10112 1011210-1 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 04/26/2017 Terms of Use: http://spiedigitallibrary.org/ss/termsofuse.aspx