Magnetically Tunable Terahertz Isolator Based on Structured Semiconductor Magneto Plasmonics

A tunable terahertz (THz) isolator based on a periodically structured semiconductor magneto plasmonics is proposed. The unique photonic band-gap and one-way transmission property of this structure with different magnetic fields and temperature are investigated in the THz regime. The numerical results show the proposed isolator has a bandwidth of 80 GHz with the maximum isolation of higher than 90 dB and a low insertion loss of 5%. The central operating frequency of this isolator can be broadly tuned from 1.4 to 0.9 THz by changing the external magnetic field from 0.6 to 1.6 Tesla at 195 K. This low-loss high isolation broadband nonreciprocal THz transmission mechanism has great potential applications in promoting the performances of THz application systems.