100 GHz wide-band HTS mixer antenna with phase control

Here we report on the millimeter-wave performance of high-Tc superconducting (HTS) Josephson junctions on MgO substrates, fabricated using a focused Ga ion beam (FIB) technique. The 6 junctions spaced 1.5 /spl mu/m apart from each other occupied 7.5 /spl mu/m. The 6 junctions can modulate even the 1000 GHz electromagnetic wave with nearly equal phase. We applied the YBCO series junction to a millimeter wave mixer with a log-periodic antenna. The HTS junction mixer and the log-periodic antenna are expected to have a function of flat frequency response up to THF. First, we measure wide frequency band responsibility for mixing function below 100 GHz. Next, we observe the HTS mixer-antenna performance as fundamental and harmonic mixers in the wide frequency range up to 100 GHz. Finally, the IF output phases can be changed within 1 dB of IF output power differences.