2018/08/31 by Raphaël Pestourie, Carlos Pérez-Arancibia, Zin Lin +3 · 263 citations
Engineering · Materials Science · Physics and Astronomy · #Advanced Antenna and Metasurface Technologies #Diffraction #Electromagnetic Scattering and Analysis #Inverse #Inverse problem #Inverse scattering problem #Maxwell's equations #Metamaterials and Metasurfaces Applications #Rigorous coupled-wave analysis #Scalar (mathematics) #Scattering #Solver #Wavelength #physics.comp-ph #physics.optics
paper · pdf · open access · doi:10.1364/oe.26.033732
published in Optics Express 26(26), 33732 (Optica Publishing Group) · 18 pages, 8 figures
openalex publication_date 2018/12/12 · arxiv created 2018/12/14 · arxiv updated 2018/12/17 · openalex created_date 2019/06/27 · openalex updated_date 2026/08/05
We present a computational framework for efficient optimization-based "inverse design" of large-area "metasurfaces" (subwavelength-patterned surfaces) for applications such as multi-wavelength/multi-angle optimizations, and demultiplexers. To optimize surfaces that can be thousands of wavelengths in diameter, with thousands (or millions) of parameters, the key is a fast approximate solver for the scattered field. We employ a "locally periodic" approximation in which the scattering problem is approximated by a composition of periodic scattering problems from each unit cell of the surface, and validate it against brute-force Maxwell solutions. This is an extension of ideas in previous metasurface designs, but with greatly increased flexibility, e.g. to automatically balance tradeoffs between multiple frequencies or to optimize a photonic device given only partial information about the desired field. Our approach even extends beyond the metasurface regime to non-subwavelength structures where additional diffracted orders must be included (but the period is not large enough to apply scalar diffraction theory).