High-Tc Superconducting Josephson Junction Harmonic Mixers with Stub Tuners on Integrated Bowtie Antennas

Ordinary mixers can hardly meet the requirements in terahertz (THz) communications due to low-power and expensive THz sources. Sensitive harmonic have been widely studied avoid this problem, owing fact that higher number of harmonics, lower local oscillator (LO) frequency, cost. High-Tc superconducting (HTS) Josephson junction (JJ) are performing candidates for receiver frontends because advantages excellent sensitivity, wide bandwidth, high low LO power requirement. However, normal-state resistance HTS JJ is so traditional antennas difficult match it. In other words, it quite a challenge input impedance antennas, especially fed by coplanar striplines (CPSs). work, based on structure bowtie, two types stub tuners were integrated decrease bowtie antenna as improve coupling efficiency between JJ. Furthermore, YBa2Cu3O7-δ (YBCO) coupled with proposed structures CPSs fabricated measured. The measurements show mixer pair open-end stubs achieves up 88 conversion −69.6 dB. contrast, lumped-element only attains 30 −73.4 Additional numerical simulations indicate enhanced when complex explicitly considered. Compared has largest number. This work paves way future application low-frequency low-cost communications.