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arXiv · 2111.06570

A Characterization of Quantum Gaussian States in Terms of Annihilation Moments

Jorge R. Bolaños-Servín·Roberto Quezada·Josué I. Rios-Cangas
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Abstract

We give a rigorous definition of moments of an unbounded observable with respect to a quantum state in terms of Yosida's approximations of unbounded generators of contractions semigroups. We use this notion to characterize Gaussian states in terms of annihilation moments. As a by-product, rigorous formulae for the mean value vector and the covariance matrix of a Gaussian state are obtained.

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Jorge R. Bolaños-Servín, Roberto Quezada, Josué I. Rios-Cangas. 2021-11-12. A Characterization of Quantum Gaussian States in Terms of Annihilation Moments. https://doi.org/10.1016/s0034-4877(22)00081-7

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