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arXiv · 2507.20015

Spin-Type Photonic Topological Insulators on a Rhombic Lattice

Robert J. Davis·Daniel F. Sievenpiper
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Abstract

A simplified model of a metallic spin-type photonic topological insulator on a rhombic lattice is presented and analyzed. Instead of the more commonly used hexagonal unit cells, a reduced symmetry rhombus is employed, which is both simpler and allows for easier integration into more traditional microwave systems. The non-trivial nature of the transport is shown via direct calculation of the structure's spin-projected Berry curvature and Wilson loop spectra, as well as by a systematic investigation of a reduced symmetry tight-binding model based off the Kane-Mele Hamiltonian. Device implementations are shown for a range of non-trivial configurations.

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Robert J. Davis, Daniel F. Sievenpiper. 2025-07-26. Spin-Type Photonic Topological Insulators on a Rhombic Lattice. https://arxiv.org/abs/2507.20015

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