THz communication has important applications in high-speed ultra wideband wireless access networks.As one of the key devices in the THz communication systems
its study is of major significance.This paper proposes a novel compound lattice photonic crystal-based multi-wavelength THz optical switch
which can effectively perform the on/off control of quadruplewavelength THz waves.Simulation is conducted by using the FDTD method in the RSOFT.The results show that its extinction ratio is 40 dB
the insertion loss 0.109 dB and the switching rate 5.55 GHz and it has important application potential in future wireless optical communications.