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arXiv · 2504.10219

Inverse design of multiresonance filters via quasi-normal mode theory

Mo Chen·Steven G. Johnson·Aristeidis Karalis
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Abstract

We present a practical methodology for inverse design of compact high-order/multiresonance filters in linear passive 2-port wave-scattering systems, targeting any desired transmission spectrum (such as standard pass/stop-band filters). Our formulation allows for both large-scale topology optimization and few-variable parametrized-geometry optimization. It is an extension of a quasi-normal mode theory and analytical filter-design criteria (on the system resonances and background response) derived in our previous work. Our new optimization-oriented formulation relies solely on a scattering solver and imposes these design criteria as equality constraints with easily calculated (via the adjoint method) derivatives, so that our algorithm is numerically tractable, robust, and well-suited for large-scale inverse design. We demonstrate its effectiveness by designing 3rd- and 4th-order elliptic and Chebyshev filters for photonic metasurfaces, multilayer films, and electrical LC-ladder circuits.

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BibTeXRIS

Mo Chen, Steven G. Johnson, Aristeidis Karalis. 2025-04-14. Inverse design of multiresonance filters via quasi-normal mode theory. https://doi.org/10.1364/oe.579219

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