Terahertz Antenna Characterized by High Temperature Superconducting YBCO Grain Boundary Josephson Junction

We apply a YBa 2 Cu 2 O x (YBCO) grain boundary (GB) Josephson junction to characterize a meander antenna loaded with a bowtie. The first-order Shapiro step height and the voltage responsivity of the detector are measured to seek the resonance frequency of the antenna. This research indicates that the bowtie loaded meander antenna is matched to the impedance of a 4-Jlm-wide junction at 219 GHz in a quasi-optical system within a quartz hyper-hemisphere lens.