Single nanowire photomixer for reliable and high frequency continuous wave terahertz generation

A new type of continuous-wave (CW) terahertz (THz) photomixer was fabricated using a single nanowire (Ø 120 nm) on low-temperature-grown (LTG) GaAs. The small diameter of the nanowire reduces the device capacitance by a factor of more than 10 compared to photomixers with conventional interdigital fingers. Furthermore, the single nanowire can handle currents > 20 mA without electromigration enabling reliably high photocurrents. Thus, these nanowire properties offer the potential for the fabrication of high frequency photomixers with cut-off frequencies > 5 THz and extremely reliable operation.