A Terahertz Slab Photonic Crystal Circulator

This study investigates a terahertz circulator based on slab photonic crystal. The slab circulator coupled to stander waveguide through a tapered slab structure. To further enhance impedance matching, a ridge structure is incorporated within the photonic crystal wave-guides. The circulator exhibits excellent transmission performance near the center frequency 0.225THz, achieving isolation is better than 20 dB, with insertion loss lower than 1 dB. These results demonstrate the potential of PC circulator for high-efficiency terahertz communication systems, offering low loss and strong isolation characteristics.