Fullwave Maxwell inverse design of axisymmetric, tunable, and multi-scale multi-wavelength metalenses Christiansen, Rasmus E. Lin, Zin Roques-Carmes, Charles Salamin, Yannick Kooi, Steven E. Joannopoulos, John D. Soljačić, Marin Johnson, Steven G. ddc:530 We demonstrate new axisymmetric inverse-design techniques that can solve problems radically different from traditional lenses, including reconfigurable lenses (that shift a multi-frequency focal spot in response to refractive-index changes) and widely separated multi-wavelength lenses (λ = 1 µm and 10 µm). We also present experimental validation for an axisymmetric inverse-designed monochrome lens in the near-infrared fabricated via two-photon polymerization. Axisymmetry allows fullwave Maxwell solvers to be scaled up to structures hundreds or even thousands of wavelengths in diameter before requiring domain-decomposition approximations, while multilayer topology optimization with ∼105 degrees of freedom can tackle challenging design problems even when restricted to axisymmetric structures. Optica Publishing Group 2020 info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/21637 Christiansen RE, Lin Z, Roques-Carmes C, et al. Fullwave Maxwell inverse design of axisymmetric, tunable, and multi-scale multi-wavelength metalenses. <i>Optics Express</i>. 2020;28(23):33854-33868. doi:<a href="https://doi.org/10.1364/oe.403192">10.1364/oe.403192</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1364/oe.403192 info:eu-repo/semantics/altIdentifier/issn/1094-4087 info:eu-repo/semantics/altIdentifier/arxiv/2007.11661 info:eu-repo/semantics/altIdentifier/pmid/33182865 info:eu-repo/semantics/openAccess