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arXiv · 1903.09370

Phase-preserving linear amplifiers not simulable by the parametric amplifier

A. Chia·M. Hajdusek·R. Nair·R. Fazio·L. C. Kwek·V. Vedral
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Abstract

It is commonly accepted that a parametric amplifier can simulate a phase-preserving linear amplifier regardless of how the latter is realized [Caves et al., Phys. Rev. A 86, 063802 (2012)]. If true, this reduces all phase-preserving linear amplifiers to a single familiar model. Here we disprove this claim by constructing two counterexamples. A detailed discussion of the physics of our counterexamples is provided. It is shown that a Heisenberg-picture analysis facilitates a microscopic explanation of the physics. This also resolves a question about the nature of amplifier-added noise in degenerate two-photon amplification.

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A. Chia, M. Hajdusek, R. Nair, R. Fazio, L. C. Kwek, V. Vedral. 2019-03-22. Phase-preserving linear amplifiers not simulable by the parametric amplifier. https://doi.org/10.1103/physrevlett.125.163603

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