Magnetically Controlled THz three-routing Switch based on Magnetic Photonic Crystals

We propose and numerically investigate magnetically controlled THz three-routing switch with highly switching contrast in two-dimensional photonic crystals, which introduced four waveguide defects and a square rod of ferrite material in the center of the structure. The four square rods around the ferrite are replaced with triangular rods to reduce the reflection of the incident wave. The maximum photonic band gap can be obtained by optimizing the side length and rotation angle of the square rods. The optical properties of system are investigated by finite element method. It demonstrates that the switching contrast is up to 45dB at the optimized operating frequency. In addition, magneto-optical materials with specific properties can be selected according to different wavelengths to realize optical functional devices of different bands. Therefore, it has great application prospect in the tunable and integrated optical devices.