Edge mode in nonreciprocal photonic crystal waveguide: manipulating the unidirectional electromagnetic pulse dynamically

A symmetrical magneto-optical photonic crystal under two equal and opposite magnetic fields is designed to generate a one-way edge mode, which cannot be reflected by the strong defect, a perfect electrical conductor, indicating immunity to strong defect. Partial reversal of electromagnetic pulse is realized when directions of applied magnetic fields are reversed, suggesting that we can dynamically manipulate the electromagnetic edge mode in such a one-way waveguide by tuning directions of the external magnetic fields, which may have potential applications in microwave engineering.