2019/01/19 by A.K. Mukherjee, A. Mukherjee, C. T. Ellis +25
Engineering · Materials Science · Physics and Astronomy · #Condensed matter physics #Faraday effect #Graphene research and applications #Kerr effect #Magnetic field #Magneto-Optical Properties and Applications #Magneto-optic Kerr effect #Materials science #Nanotechnology #Optics #Optoelectronics #Physics #Plasmonic and Surface Plasmon Research #Refractive index #Substrate (aquarium) #Thin film #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.99.085440
15 pages, 4 figures
arxiv created 2019/01/19 · openalex created_date 2019/02/21 · openalex publication_date 2019/02/27 · arxiv updated 2019/03/27 · openalex updated_date 2026/08/05
We report a giant enhancement of the midinfrared magneto-optical complex Kerr angle (polarization change of reflected light) in a variety of materials grown on SiC. In epitaxially grown multilayer graphene, the Kerr angle is enhanced by a factor of 68, which is in good agreement with Kerr signal modeling. Strong Kerr enhancement is also observed in Fe films grown on SiC and Al-doped bulk SiC. Our experiments and modeling indicate that the enhancement occurs at the high-energy edge of the SiC reststrahlen band where the real component of the complex refractive index \stackrel\ifmmode \else \~\fin passes through unity. Furthermore, since the signal is greatly enhanced when \stackrel\ifmmode \else \~\fin=1, the enhancement is predicted to exist over the entire visible and IR spectrum for a free-standing film. We also predict similar giant enhancement in both Faraday (transmission) and Kerr rotation for thin films on a metamaterial substrate with refractive index \stackrel\ifmmode \else \~\fin=\ensuremath-1. This paper demonstrates that the substrate used in magneto-optical Kerr effect (MOKE) measurements must be carefully chosen when investigating magneto-optical materials with weak MOKE signals or when designing MOKE-based optoelectronic devices.