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arXiv · 2609.39610

Circuit-Based Dispersion Analysis of Periodic Cross-Shaped Unit Cells with Dirac Characteristics

Mahyar Mehri Pashaki·Mohammad Hossein Koohi Ghamsari·Mohammad Memarian
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Abstract

In this paper, the dispersion behavior of periodic cross-shaped unit cells is investigated with emphasis on Dirac-type dispersion using an equivalent circuit modeling approach. Two unit-cell geometries, including a simple cross structure and a modified configuration with a central patch, are analyzed using full-wave eigenmode simulations and scattering-parameter-based dispersion extraction. An equivalent circuit model is developed to capture the dominant coupling mechanisms and accurately reproduce the dispersion characteristics near the $Γ$-point. The results demonstrate that the proposed circuit model exhibits good agreement with full-wave simulations and provides a physically intuitive framework for analyzing stopband behavior and mode degeneracy. Furthermore, the limitations of S-parameter-based dispersion extraction in the presence of low-Q radiative modes are highlighted.

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Mahyar Mehri Pashaki, Mohammad Hossein Koohi Ghamsari, Mohammad Memarian. 2026-09-30. Circuit-Based Dispersion Analysis of Periodic Cross-Shaped Unit Cells with Dirac Characteristics. https://arxiv.org/abs/2609.39610

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