Applied Superconductivity

Picosecond nodal testing of centimeter-size superconducting Nb microstrip interconnects

Marc Currie, Chia‐Chi Wang, Roman Sobolewski, Thomas Y. Hsiang

Published Oct 1, 1999• 2 citations

Abstract

We have implemented a low-temperature electro-optic sampling system for non-invasive, nodal testing of superconducting Nb integrated circuits. With submillivolt sensitivity and a subpicosecond temporal response, this system has been used to perform nodal analysis on rapid-single-flux quantum (RSFQ) devices and superconducting microstrip interconnects. Here we demonstrate that by measuring the propagation of 6-ps-wide pulses at various test nodes, we are able to fully characterize a superconducting microstrip waveguide the size of an entire chip. The transmission line was selected not only to perform the first complete characterization of a superconducting microstrip, but also to demonstrate full nodal testing of a foundry-fabricated RSFQ integrated circuit. Finally, our results provided much-needed feedback for improving computer simulations of superconducting digital circuits.

DOI: 10.1016/s0964-1807(99)00048-4

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