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arXiv · 1305.7051

The pumpistor: a linearized model of a flux-pumped SQUID for use as a negative-resistance parametric amplifier

K. M. Sundqvist·S. Kintaş·M. Simoen·P. Krantz·M. Sandberg·C. M. Wilson·P. Delsing
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Abstract

We describe a circuit model for a flux-driven SQUID. This is useful for developing insight into how these devices perform as active elements in parametric amplifiers. The key concept is that frequency mixing in a flux-pumped SQUID allows for the appearance of an effective negative resistance. In the three-wave, degenerate case treated here, a negative resistance appears only over a certain range of allowed input signal phase. This model readily lends itself to testable predictions of more complicated circuits.

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K. M. Sundqvist, S. Kintaş, M. Simoen, P. Krantz, M. Sandberg, C. M. Wilson, P. Delsing. 2013-05-30. The pumpistor: a linearized model of a flux-pumped SQUID for use as a negative-resistance parametric amplifier. https://doi.org/10.1063/1.4819881

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