Photonic Cyclic Orbit Bound to a Single Weyl Point
Phys. Rev. Lett. 136, 103801 – Published 9 March, 2026
DOI: https://doi.org/10.1103/bpjc-8kz7
Abstract
Weyl orbits are topologically protected cyclotron trajectories that connect Weyl nodes of opposite chiralities in momentum space, coupling bulk chiral Landau levels and surface Fermi arcs to produce quantum oscillations under static magnetic fields. While well-studied in condensed matter systems, their photonic analogs remain elusive due to the difficulty in generating global pseudomagnetic fields. Here, we overcome these limitations by engineering a pseudomagnetic field domain wall, enabling a novel photonic cyclic orbit (PCO) bound to a single Weyl point, unlike conventional Weyl orbits that link paired WPs. In the PCO, photons traversing the domain wall experience pseudomagnetic field reversal and flipping of momentum-space motion along Fermi arcs, forming a closed trajectory through a single Weyl point. Experimentally, we observe a photonic analog of quantum oscillations, manifested as discrete photonic resonances, and PCO states in the real space, comprising Fermi-arc surface states and chiral zero modes, providing definitive evidence of photonic Weyl orbits. Our Letter establishes a new paradigm for topological cyclic orbits and opens practical pathways for three-dimensional light manipulation.