Double-side-input subharmonic mixer using planar bowtie antenna based on Fermi-level managed barrier diodes on SiC platform

A terahertz-wave subharmonic mixer receiving RF input and local oscillator (LO) signals from the opposite side of a planar antenna was developed based on epi-layer-transferred Fermi-level managed barrier diodes on a SiC substrate. The developed mixer mounted on a Si hyper-hemispherical lens with a transimpedance amplifier exhibited a minimum noise-equivalent power as low as 6 × 10-19 W/Hz at RF and LO frequencies of 306 and 151 GHz, respectively. Comparison of signal-introduction configurations revealed that a single planar antenna simultaneously acted as an antenna for RF and LO signals as well as a signal combiner for mixing detection.