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arXiv · 1009.4673

Noise Performance of Lumped Element Direct Current Superconducting Quantum Interference Device Amplifiers in the 4 GHz-8 GHz Range

Lafe Spietz·Kent Irwin·Minhyea Lee·Jose Aumentado
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Abstract

We report on the noise of a lumped element Direct Current Superconducting Quantum Interference Device amplifier. We show that the noise temperature in the 4 GHz-8 GHz range over ranges of 10's of MHz is below 1 kelvin (three photons of added noise), characterize the overall behavior of the noise as a function of bias parameters, and discuss potential mechanisms which determine the noise performance in this amplifier. We show that this device can provide more than a factor of 10 improvement in practical system noise over existing phase-preserving microwave measurement systems in this frequency band.

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Lafe Spietz, Kent Irwin, Minhyea Lee, Jose Aumentado. 2010-09-23. Noise Performance of Lumped Element Direct Current Superconducting Quantum Interference Device Amplifiers in the 4 GHz-8 GHz Range. https://doi.org/10.1063/1.3497008

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