Shaping Bulk Fermi Arcs in the Momentum Space of Photonic Crystal Slabs

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Frau, Luigi, Zanotti, Simone, Ferrier, Lydie, Gerace, Dario, Nguyen, Hai Son
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866911007562006528
author Frau, Luigi
Zanotti, Simone
Ferrier, Lydie
Gerace, Dario
Nguyen, Hai Son
author_facet Frau, Luigi
Zanotti, Simone
Ferrier, Lydie
Gerace, Dario
Nguyen, Hai Son
contents Exceptional points (EPs) are special spectral degeneracies of non-Hermitian operators: at the EP, the complex eigenvalues coalesce, i.e., they become degenerate in both their real and imaginary parts. In two-dimensional (2D) photonic crystal lattices, these elements can be tailored through structural engineering. In particular, it is known that a quadratic degeneracy in the photonic band structure can be split into a pair of Dirac points (DPs) by breaking one of the unit cell symmetries, and each DP can be further split into a pair of EPs by introducing losses. Each EP of the pair is then connected by an open isofrequency curve, called the bulk Fermi arc (BFA). In this work, we introduce a simplified effective Hamiltonian model accounting for the main physical properties of these EPs and BFAs. Then, we systematically investigate, through numerical simulations, how EPs as well as the related BFA depend on the type and amount of broken symmetries in the given 2D unit cell of a realistic photonic crystal slab implementation. Our results show that it is possible to tailor the position and distance of the EP pair in reciprocal space, as well as the curvature and orientation of the associated BFA, by deterministically tuning the unit cell structure. Importantly, the symmetry-breaking strategy we propose is general and can be applied to a broad range of photonic crystal designs beyond the specific example studied here. This approach opens new possibilities for exploiting EPs in applications involving photonic crystal lattices in, e.g., light-emitting devices or fundamental physics studies.
format Preprint
id arxiv_https___arxiv_org_abs_2506_13698
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Shaping Bulk Fermi Arcs in the Momentum Space of Photonic Crystal Slabs
Frau, Luigi
Zanotti, Simone
Ferrier, Lydie
Gerace, Dario
Nguyen, Hai Son
Optics
Mesoscale and Nanoscale Physics
Exceptional points (EPs) are special spectral degeneracies of non-Hermitian operators: at the EP, the complex eigenvalues coalesce, i.e., they become degenerate in both their real and imaginary parts. In two-dimensional (2D) photonic crystal lattices, these elements can be tailored through structural engineering. In particular, it is known that a quadratic degeneracy in the photonic band structure can be split into a pair of Dirac points (DPs) by breaking one of the unit cell symmetries, and each DP can be further split into a pair of EPs by introducing losses. Each EP of the pair is then connected by an open isofrequency curve, called the bulk Fermi arc (BFA). In this work, we introduce a simplified effective Hamiltonian model accounting for the main physical properties of these EPs and BFAs. Then, we systematically investigate, through numerical simulations, how EPs as well as the related BFA depend on the type and amount of broken symmetries in the given 2D unit cell of a realistic photonic crystal slab implementation. Our results show that it is possible to tailor the position and distance of the EP pair in reciprocal space, as well as the curvature and orientation of the associated BFA, by deterministically tuning the unit cell structure. Importantly, the symmetry-breaking strategy we propose is general and can be applied to a broad range of photonic crystal designs beyond the specific example studied here. This approach opens new possibilities for exploiting EPs in applications involving photonic crystal lattices in, e.g., light-emitting devices or fundamental physics studies.
title Shaping Bulk Fermi Arcs in the Momentum Space of Photonic Crystal Slabs
topic Optics
Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2506.13698