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arXiv · 2007.11661

Fullwave Maxwell inverse design of axisymmetric, tunable, and multi-scale multi-wavelength metalenses

Rasmus E. Christiansen·Zin Lin·Charles Roques Carmes·Yannick Salamin·Steven E. Kooi·John D. Joannopoulos·Marin Soljačić·Steven G. Johnson
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Abstract

We demonstrate new axisymmetric inverse-design techniques that can solve problems radically different from traditional lenses, including \emph{reconfigurable} lenses (that shift a multi-frequency focal spot in response to refractive-index changes) and {\emph{widely separated}} multi-wavelength lenses ($\lambda = 1\,\mu$m and $10\,\mu$m). 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 $\sim 10^5$ degrees of freedom can tackle challenging design problems even when restricted to axisymmetric structures.

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BibTeXRIS

Rasmus E. Christiansen, Zin Lin, Charles Roques Carmes, Yannick Salamin, Steven E. Kooi, John D. Joannopoulos, Marin Soljačić, Steven G. Johnson. 2020-07-22. Fullwave Maxwell inverse design of axisymmetric, tunable, and multi-scale multi-wavelength metalenses. https://doi.org/10.1364/oe.403192

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