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Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Periodic and aperiodic superconducting microstructures

John B. Ketterson, Paul R. Auvil, David John Morgan, Stevan R. Maglic, Christopher D. Thomas, Ivan P. Nevirkovets

Published Dec 9, 1998• 0 citations

Abstract

We summarize some recent activities of our group involving e-beam and optically patterned, Nb-based, superconducting nanostructures, as well as related computer modeling studies. The devices described are i) Fiske cavities buried in a Nb base layer and driven by an overlying Nb/AlOx/Nb Josephson oscillator junction, ii) Nb/AlOx/Al/AlOx/Nb five-layer double junctions which Maezava and Shoji have observed to perform as nonhysteretic SNS Josephson single junctions, and iii) critical current measurements on e-beam patterned, 2D arrays of periodic and aperiodic ferromagnetic Ni 'dots' embedded in a Nb film. We also describe a method of 'base-electrode planarization' leading to more uniform junction formation. The computer modeling studies involve the stable and unstable solution states in a static magnetic field of current-biased single and double Josephson junctions.

DOI: 10.1117/12.332443

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Measurement of Specific Capacitance for Nb/Al–AlO

_{x}

/Nb Josephson Junctions in Single-Flux Quantum Circuit Applications

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