Novel optical controllable terahertz wave switch

We study theoretically and demonstrate experimentally light controllable terahertz wave switch. When the modulated optical excitation source is used to irradiate a high resistivity silicon wafer, a novel controllable terahertz wave switch is achieved. The results show that the ON–OFF response time is less than 150 ms and the attenuation of the novel terahertz wave switch is more than 20 dB at frequency of 0.315 THz.