Goos–Hänchen Shift Spatially Resolves Magneto-Optical Kerr Effect Enhancement in Magnetoplasmonic Crystals

We report on how observation of the Goos–Hänchen (GH) shift can be used to spatially resolve the transverse magneto-optical Kerr effect (TMOKE) enhancement in all-nickel magnetoplasmonic crystals (MPCs). First, the excitation of surface plasmons in the MPCs leads to a 15.3 μm (18λ) GH shift. Then, in the presence of a transverse magnetic field, the modulation of the lateral spatial intensity distribution of the reflected light TMOKE(x), caused by the GH shift, reaches 4.7% in the experiment. The spatially resolved TMOKE(x) values are several times higher compared to those from conventional TMOKE measurements in the MPCs. The concept of the spatially resolved magneto-optical effects under GH shift can be further extended to other magnetophotonic nanodevices for additional enhancing magneto-optical effects, sensing, and light modulation applications.