Embedded HEMT/metamaterial composite devices for active terahertz modulation

The first gallium arsenide (GaAs) High Electron Mobility Transistor (HEMT) based metamaterial is demonstrated and used to modulate an electromagnetic signal of 0.55 THz at speeds up to 10MHz. The devices are constructed using a commercial GaAs technology primarily used for mobile phone technology. The metamaterial was constructed using a classical Double Electric Split Ring Resonator (DESRR) using a gold metal layer available in the technology. The Scanning Electron Microscope (SEM) photograph shows one element of the array. The HEMT was placed underneath the split gap with the drain and source connected to the split gap of the resonator. This allows to change the property of the metamaterial by applying gate bias voltage to the HEMT switch.