Giant Magneto-Optical Kerr Enhancement from Films on SiC Due to the Optical Properties of the Substrate
Abstract
We report a giant enhancement of the mid-infrared (MIR) 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 (n) over tilde passes through unity. Furthermore, since the signal is greatly enhanced when (n) over tilde = 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 (n) over tilde = -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.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 27, 2019
- Accession Number
- AD1099191
Entities
People
- Arunabh Mukherjee
- C. Jr R. Eddy
- C. T. Ellis
- D. Kurt Gaskill
- E. Oliverio
- Evan R. Glaser
- Gang Wang
- H. Zeng
- J. Cerne
- J. G. Tischler
- J. L. Tedesco
- M. M. Arik
- P. Fowler
- P. Taheri
- R. L. Myers-ward
- Y. Liu
Organizations
- United States Naval Research Laboratory