Theoretical seminar | 30 August 2023

We present theory and methods of design of dielectric metasurfaces for the anomalous refraction at near-grazing directions and for the maximum optical chirality. It is shown that Fourier-metasurfaces – thin layers of dielectrics with smooth shallow periodic reliefs – can deflect incident light into a single outgoing diffraction channel by angles exceeding 80°. It is also demonstrated how one can design maximum chiral metasurfaces, which are transparent to the waves of one circular polarization and completely block the waves of the opposite polarization. We discuss recent experimental realizations of such metasurfaces and their potential applications.

Main paper/arXiv, related to the seminar, and other references

[1] A.A. Antonov et al., Corrugated silicon metasurface optimized within the Rayleigh hypothesis for anomalous refraction at large angles, J. Opt. Soc. Am. B, 36, 2118 (2019), https://doi.org/10.1364/JOSAB.36.002118
[2] A.A. Antonov et al., Dielectric Fourier metasurfaces as wide-angle Y-junction switches, J. Opt., 23, 125103 (2021), https://doi.org/10.1088/2040-8986/ac3298
[3] M.V. Gorkunov et al., Metasurfaces with maximum chirality empowered by bound states in the continuum, Phys. Rev. Lett., 125, 9, 093903 (2020), https://doi.org/10.1103/PhysRevLett.125.093903
[4] M.V. Gorkunov et al., Bound states in the continuum underpin near-lossless maximum chirality in dielectric metasurfaces, Adv. Opt. Mat., 9, 2100797 (2021),
https://doi.org/10.1002/adom.202100797
[5] S. Kim et al., Chiral electroluminescence from thin-film perovskite metacavities, Sci. Adv., 9, 26 (2023), https://doi.org/10.1126/sciadv.adh0414