One-way bulk-boundary coupling in a two-dimensional antiferromagnetic photonic Dirac semimetal
Phys. Rev. A 112, 053517 – Published 18 November, 2025
DOI: https://doi.org/10.1103/vz11-nn51
Abstract
Recently discovered antichiral edge states, which are pinned to a pair of offset Dirac points with different degenerate energies, exhibit the same propagating direction along parallel boundaries. However, few studies focus on accompanying opposite bulk propagation in terms of energy conservation in nondissipative systems. Here, we fabricate a two-dimensional honeycomb-lattice antiferromagnetic photonic crystal to construct a photonic Dirac semimetal. Both nonreciprocal bulk states and antichiral edge states are observed in the vicinity of the Dirac point frequency in microwave experiments. Using a rhombus-shaped sample, we realize one-way bulk to boundary and boundary to bulk couplings. Furthermore, we demonstrate a nonreciprocal tunnelinglike phenomenon from the upper to the lower boundaries across the bulk region. Our results highlight the underlying relation between the nonreciprocal bulk and antichiral edge states, which may provide an ideal strategy to design perfect bulk-boundary couplers, splitters, and various other applications.
