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arXiv · 1610.07893

Non-Markovianity Hierarchy of Gaussian Processes and Quantum Amplification

Pietro Liuzzo-Scorpo·Wojciech Roga·Leonardo A. M. Souza·Nadja K. Bernardes·Gerardo Adesso
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Abstract

We investigate dynamics of Gaussian states of continuous variable systems under Gaussianity preserving channels. We introduce a hierarchy of such evolutions encompassing Markovian, weakly and strongly non-Markovian processes, and provide simple criteria to distinguish between the classes, based on the degree of positivity of intermediate Gaussian maps. We classify all single-mode phase-insensitive Gaussian channels according to their non-Markovianity degree, and show that weak non-Markovianity has an operational significance as it leads to temporary amplification of Gaussian inputs beyond the fundamental quantum limit. Explicit examples and applications are discussed.

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Pietro Liuzzo-Scorpo, Wojciech Roga, Leonardo A. M. Souza, Nadja K. Bernardes, Gerardo Adesso. 2017-02-01. Non-Markovianity Hierarchy of Gaussian Processes and Quantum Amplification. https://doi.org/10.1103/physrevlett.118.050401

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