High-Speed Terahertz Modulation Based on the Control of Metamaterial Mode to Waveguide Mode

In the traditional terahertz spatial modulator, the scale of the metamaterial must be equivalent to the area of the terahertz spot in free space to obtain effective terahertz modulation. Large-scale artificial microstructure arrays increase the complexity of metamaterial circuits, which leads to problems such as mode parasitic and impedance mismatches inside the metamaterial. In order to effectively reduce the scale of the metamaterial array, so as to manipulate the terahertz wave more efficiently, in this paper, we propose a technical scheme for loading the spatial modulator with waveguide. By regulating the carrier concentration of 2DEG in metamaterial chip, the efficient control of metamaterial mode to waveguide mode has been realized. Static modulation depth of this device can reach up to 13.5dB. More importantly, in the dynamic test, 8 GHz sinusoidal signals was received by a THz mixer receiver. It may provide a way to achieve high-performance active devices in THz wireless communication system.