Harnessing Selective State Space Models to Enhance Semianalytical Design of Fabrication-Ready Multilayered Huygens' Metasurfaces: Part I - Field-based Semianalytical Synthesis

TL;DR

This paper develops an efficient semianalytical model for designing multilayer Huygens' metasurfaces, enabling rapid, accurate synthesis of fabrication-ready meta-atoms with wideband and dual-polarization capabilities, validated through full-wave simulations.

Contribution

It extends analytical models to densely packed Jerusalem-cross meta-atoms, creating a rapid synthesis framework for Huygens' metasurfaces, complemented by a scaling method for wideband response prediction.

Findings

Accurate semianalytical model for densely packed Jerusalem-cross meta-atoms.

Rapid synthesis of low-reflection, dual-polarized metasurfaces using a phase-leg-length lookup table.

Validation through a full-wave-verified metalens demonstrating effective beam manipulation.

Abstract

Planar metasurfaces can profoundly control electromagnetic scattering. At microwave frequencies, such devices are typically implemented using multilayer cascades of patterned metallic sheets, whose design often requires time-consuming full-wave optimization. Here, we extend analytical models originally developed for sparse loaded-wire metagratings to accurately describe densely packed Jerusalem-cross meta-atoms embedded in standard printed circuit board (PCB) dielectric stacks. The model captures both near- and far-field coupling within and between layers, enabling efficient prediction of the dual-polarized response. Using this framework, we identify highly transmissive meta-atoms whose phase is controlled by the leg lengths of the Jerusalem crosses (microscopic design stage). This (phase)-(leg-length) "lookup table" allows rapid synthesis of Huygens' metasurfaces (macroscopic design stage), demonstrated through a full-wave-validated metalens exhibiting low-reflection beam manipulation. Notably, we implement a judicious scaling method to further extend the model to predict wideband meta-atom responses. In the companion paper (Part II), a hybrid machine-learning approach leverages this semianalytical framework to enhance accuracy without requiring the conventional exhaustive full-wave training, enabling ultrafast inverse design across the full parameter space. Overall, the presented methodology -- the standalone semianlytical scheme (Part I) and the machine-learning enhanced version (Part II) -- establishes an effective open-source toolkit for versatile, rapid, and highly accurate synthesis of fabrication-ready dual-polarized transmissive Huygens' meta-atoms and metasurfaces.