T-shaped optical circulator based on coupled magneto-optical rods and a side-coupled cavity in a square-lattice photonic crystal

► We design a T-shaped three-port circulator in a magneto-photonic crystal. ► A single-direction 90° light-bending is realized by coupling two magneto-optical rods. ► Two paths of 90° light-bending are effectively combined by a side-coupled cavity. ► The designed circulator has compact structure and high efficiency. ► The circulator can be used to build photonic crystal integrated optical circuits.