Bandwidth-enhanced moiré superchiral optical field in a nodal ring photonic crystal
Phys. Rev. B 113, 125429 – Published 24 March, 2026
DOI: https://doi.org/10.1103/qdyx-8cg8
Abstract
On-chip optical superchiral fields are usually generated using nanostructures. Here we demonstrate superchiral field generation using surface waves in a one-dimensional photonic crystal (PhC). The PhC supports nodal rings featuring a bandwidth-enhanced, all-angle degenerate dispersion for transverse magnetic (TM) and transverse electric (TE) surface modes. This unique degeneracy is harnessed to create simultaneous electric field and magnetic field skyrmion bags, resulting in a moiré superchiral field superlattice on the flat crystal surface. We show that the distribution of the superchirality can be modulated by the moiré angle and orbital angular momentum of the excitation scheme and the handedness of chirality is determined by the phase difference between TM and TE waves. This work proposes a simple platform for on-chip chiral sensing using tailored superchiral fields.
