Electromagnetic waves in subwavelength metamaterial tri-layers: new interference-enabled opportunities to control and amplify Faraday’s effect

Abstract Interaction of electromagnetic waves with a three-layer system “spacer layer 1 – magneto-active (due to Faraday’s effect) layer – spacer layer 2” has been investigated. Numerical analysis and parametric optimization of the corresponding boundary problem solution demonstrate new possibilities to use such systems (for both metamaterial and “conventional” layers of subwavelength thickness) as ultra-compact nonreciprocal devices for magnetophotonics applications. Decreasing the thicknesses of the layers and of the whole tri-layer, “adding” non-magneto-active layers, and optimizing the system over wide ranges of realistic parameters can amplify (by several orders of magnitude) the magneto-optical response in comparison with the case of the single magneto-active layer (without spacer layers). The parameters related to the first few interference transmission peaks (with increasing the magneto-active layer thickness) are of the greatest interest. Varying the spacer layer parameters allows controlling transmission peaks and spectral characteristics of the tri-layers. The concept of the interference-enabled control and amplification of Faraday’s effect can be realized for various layer geometries and materials and used to develop ultrathin, relatively easy-to-manufacture devices for polarization magneto-optics and integrated optics.