Coaxial Lines and Cavities Containing High T sub c Superconducting Center Conductors

We have produced some short sections of coaxial transmission line containing ceramic, high T sub c, superconducting center conductors. These lines are about 6 inches long and 1 inch in diameter. Theoretically, a superconducting line should be essentially lossless, dispersionless and have a purely resistive impedance up to at least 10 GHz. In fact we expect that a long (>1 km) line could in principal, carry nanosecond rise time pulses with zero distortion and low loss (