Traveling wave photomixers based on low-temperature-grown Gallium Arsenide reaching 50 mA/W under 1550 nm CW illumination

In this work we present an original design of a traveling-wave photomixer (TWP) based on low-temperature-grown GaAs layer (LT-GaAs) optimized for 1550 nm wavelength excitation. The optical wave is absorbed in the LT-GaAs through an integrated silicon nitride-based waveguide. The optical waveguide is centered between two metallic contacts that serves as biasing electrodes and metallic strips of a THz coplanar waveguide. The device exhibited dc photoresponses as high as 50 mA/W.