Study Of Terahertz Photonic Crystal Based On Magneto-Optical Crystal

Terahertz (THz) technology is a rising and promising field. The development of THz technology needs not only source and detector but also kinds of functional elements. With the combination of magneto-optical crystal and photonic crystal, new isolator and circulator are both designed for THz. In this paper, detailed analysis of isolator is done from three aspects of dispersion, mode-distribution and transmission, and a unidirectional bandwidth of 0.04c/a is achieved by optimizing structure parameters. Based on this isolator, a kind of original and advanced four-port circulator with 4 YIG rods is proposed whose maximal bandwidth could achieve 0.017c/a. A narrow-bandwidth circulator with Q= 5497 is designed by merging cavity into the four-port circulator above. And another kind of islator with bandwidth of 0.017c/a is also designed by blocking one of the four ports and removing 2 YIG rods. By changing the locations of YIG rods, a kind of waveguide-cross with ultra-low cross-talk is achieved. At last, according to material parameters and equipments, samples and experimental plan are designed for microwave and THz.