T-typed photonic crystal circulator with square lattice Al2O3 rods array and NiZn-ferrite posts

Abstract This paper proposes and validates a novel T-typed magneto-photonic crystals circulator consisting of Al 2 O 3 ceramic rods array and ferrite posts. Based on the numerical simulations on the band gap of photonic crystals and the function of the circulator, the optimal isolation, insertion loss and bandwidth of the circulator are −25.92 dB, −0.064 dB and 350 MHz respectively in the calculation. The corresponding experiments are performed, which are matched well with the numerical results. At the central frequency of 10.03 GHz, the measured isolation and insertion loss of the circulator reaches −45.82 dB and −1.88 dB, respectively. The bandwidth of the circulator is about 270 MHz, which requires the isolation below the value of −20 dB. The high isolation, low loss and easy integration mean that our circulator has potential applications in communication systems.