Ultra broad band measurements on high T/sub c/ ceramic superconducting transmission lines

Transmission lines were fabricated on high-T/sub c/ ceramic conductor thin films by means of a lithographic technique. A scalar network analyzer was used to perform measurements from 10 MHz to 26.5 GHz of the transmission and reflection characteristics of superconducting transmission lines at 4.2 K, 77 K, and room temperature. The lines were fabricated from 0.8- mu m-thick YBa/sub 2/Cu/sub 3/O/sub 7/ on 1.0-mm-thick SrTiO/sub 3/ substrates. Characteristic impedance, attenuation constant, phase constant, group time delay and group velocity were calculated by a novel algorithm which is processed in real time. Time domain responses, e.g., pulse delay and waveform distortion, were also easily obtained by a computer technique. The degradation due to the etching process is investigated, and a comparison is made of copper and ceramic transmission lines.<
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