Thermally controlled magneto-optical metasurface for tunable Faraday rotation
Phys. Rev. Applied 24, 034056 – Published 22 September, 2025
DOI: https://doi.org/10.1103/f6cr-tfld
Abstract
We present a type of tunable magneto-optical metasurface performing Faraday rotation, the sign and value of which are not fixed after the structure fabrication but can be tuned in a wide range via heating of the metasurface. We demonstrate both experimentally and theoretically that the Faraday rotation angle is enhanced in the vicinity of the magnetodipole and electrodipole Mie resonances and can be changed in a wide range from to for the same metasurface at fixed wavelength of incident light under the temperature changes from 294 to 488 K. Such thermal heating can be performed by an external control laser. As laser radiation can be focused at the spots of approximately diameter, the magneto-optical response can also be tuned locally. Thus one may obtain the inhomogeneous magneto-optically induced polarization rotation distributions across the metasurface by the creation of the laser-beam patterns with the desired intensity profiles. Another possibility opened by the proposed metasurface is the self-modulation of polarization of laser light performed depending on its intensity.