Photonic antichiral edge states induced by magnetic surface plasmon resonance

Abstract

Chiral edge states are a hallmark feature of photonic Chern insulators, where waves propagate in opposite directions along two parallel edges of a strip sample. Different from the chiral edge states, at recently discovered counterintuitive antichiral edge states, where waves propagate in the same direction on the two edges, the antichiral edge states are modeled by the modified Haldane model. Here, we theoretically propose, experimentally observe the antichiral edge states induced by magnetic surface plasmon resonance, and realize the antichiral edge states in a gyromagnetic photonic crystal with rectangular lattice. Through microwave experiments and photonic band calculations, the unique properties of this antichiral edge states have been confirmed, including edge dispersion without Dirac points frequencies shift, unidirectional transmission without ancillary cladding, and the operating frequency of the edge states that can be flexibly controlled by the external magnetic field. These results extend the scope of antichiral edge states and supplement the current understanding of antichiral edge states.