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arXiv · 2010.13851

Quantum limits on noise for a class of nonlinear amplifiers

Jeffrey M. Epstein·K. Birgitta Whaley·Joshua Combes
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Abstract

Nonlinear amplifiers such as the transistor are ubiquitous in classical technology, but their quantum analogues are not well understood. We introduce a class of nonlinear amplifiers that amplify any normal operator and add only a half-quantum of vacuum noise at the output. In the large-gain limit, when used in conjunction with a noisy linear detector, these amplifiers implement ideal measurements of the normal operator.

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Jeffrey M. Epstein, K. Birgitta Whaley, Joshua Combes. 2020-10-26. Quantum limits on noise for a class of nonlinear amplifiers. https://doi.org/10.1103/physreva.103.052415

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