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Journal of Applied Physics

A vortex–antivortex pairs triggered Josephson shift register

Matteo Cirillo, Vittorio Merlo

Published Oct 15, 1995• 1 citation
Publisher

Abstract

We study the performances of a type of single-phase shift register based on flux-quanta dynamics. The system employs as a clock signal a spatially localized sinusoidal current injection in a discrete Josephson transmission line. This drive generates fluxon–antifluxon pairs which, traveling along the transmission line, move the single flux quanta stored in attractive potential wells. These wells are obtained by inserting inductive discontinuities in the transmission line. The simulations show that the device could operate in real Josephson systems with clock frequencies in the range 10–100 GHz. Good margins are found for the most critical parameters of operation.

DOI
10.1063/1.359733

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We study the performances of a type of single-phase shift register based on flux-quanta dynamics. The system employs as a clock signal a spatially localized sinusoidal current injection in a discrete Josephson transmission line. This drive generates fluxon–antifluxon pairs which, traveling along the transmission line, move the single flux quanta stored in attractive potential wells. These wells are obtained by inserting inductive discontinuities in the transmission line. The simulations show that the device could operate in real Josephson systems with clock frequencies in the range 10–100 GHz. Good margins are found for the most critical parameters of operation.
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