Tunable terahertz Kerr switching based on nonlinear polarization rotation in silicon waveguide

A compact and widely tunable terahertz (THz) all-optical Kerr switching using nonlinear polarization rotation generated by cross-phase modulation in a silicon waveguide is theoretically proposed. A switching efficiency of 83% is obtained when a π-phase shift difference between the TE and TM polarization components of the continuous-wave THz signal is achieved. Moreover, the tuning range of the THz switching is from 7.69 to 10 THz through changing the pump power. This THz all-optical switching has potential applications in THz communications and other THz switchable devices.