A.D. Rozenblit1, N.A. Olekhno2

1,2ITMO University (St. Petersburg, Russia)

1alina.rozenblit@metalab.ifmo.ru

Higher-order photonic topological insulators in the form of two-dimensional arrays of coupled resonators demonstrate the presence of edge and corner states with energies in the bulk band gap. Such states demonstrate an increased robustness to geometrical imperfections and thus are considered prospective for photonic devices at the optical and microwave frequencies. In this paper, we demonstrate that a two-dimensional higher-order photonic topological insulator can be implemented as an array of coupled split-ring resonators with dipole and quadrupole response in the GHz frequency range. By performing numerical simulations, we consider bulk band structure of infinite lattices of split-ring resonators with different parameters, as well as eigenmodes of finite resonator arrays. We demonstrate the presence of a bulk band gap and study the distributions of the electric field for bulk, edge, and corner states. The proposed approach allows for inexpensive production, the introduction of non-linearities in split-ring resonators, and the creation of three-dimensional and reconfigurable structures for experimental studies of photonic topological insulators and the development of their practical applications.

Rozenblit A.D., Olekhno N.A. Higher-order topological states in arrays of split-ring resonators with dipole and quadrupole response. Electromagnetic waves and electronic systems. 2026. V. 31. № 3. P. 88−97. DOI: https://doi.org/10.18127/j15604128-202603-10 (in Russian)

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