Highly Transparent Graphene Electrodes for CW THz Applications

Transparent graphene-based electrodes for CW THz devices are intensively investigated here. The multilayer graphene (MLG) electrodes were transferred on top of Low temperature GaAs (LT-GaAs) as photoconductive material. The high transparency of the graphene allows ~ 97% of the light to propagate through the transparent electrodes and increase the effective illuminated area. This will increase the carrier density, which leads to higher generated photocurrent. The simulation predicts more than one order of magnitude higher photocurrent can be reached by using multilayer graphene instead of a metal, such as gold. The benefits of using MLG instead of metal conductor results in a 40 times higher photocurrent than the photocurrent using gold electrodes at 20 V bias voltage.