Simulation study of terahertz detectors with ungated regions and diffusion current

Terahertz detectors based on the plasma instability are simulated. The impact of the diffusion current is investigated. It is found that the inclusion of the diffusion current into the simulation increases the resonance frequency. Moreover, the ungated region between the source contact and the gated channel region is included in the simulation. It is found that the non-vanishing source impedance originated from the ungated region introduces a huge difference on the resonance frequency.