THz/subTHz detection by asymmetrically-shaped bow-tie diodes containing 2DEG Layer

We present asymmetrically-shaped bow-tie diodes based on a modulation-doped GaAs/AlGaAs structure. One of the bow-tie leaves is metallized in order to concentrate the incident radiation into the apex of the other half which contains the 2DEG layer: Here the electrons are heated non-uniformly by incident radiation inducing a voltage signal over the ends of the device. The diode sensitivity at room temperature within 10 GHz - 0.8 THz is close to 0.3 V/W, while with an increase of frequency up to 2.52 THz it decreases due to weaker coupling. We consider options to improve the operation of the device.