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Generalized constraints on quantum amplification

U. Gavish·B. Yurke·Y. Imry
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Abstract

We derive quantum constraints on the minimal amount of noise added in linear amplification involving input or output signals whose component operators do not necessarily have c-number commutators, as is the case for fermion currents. This is a generalization of constraints derived for the amplification of bosonic fields whose components posses c-number commutators.

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U. Gavish, B. Yurke, Y. Imry. 2004-07-16. Generalized constraints on quantum amplification. https://doi.org/10.1103/physrevlett.93.250601

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