Witnessing negativity of Wigner function by estimating fidelities of catlike states from homodyne measurements

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F13%3A33144347" target="_blank" >RIV/61989592:15310/13:33144347 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1103/PhysRevA.87.062115" target="_blank" >http://dx.doi.org/10.1103/PhysRevA.87.062115</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevA.87.062115" target="_blank" >10.1103/PhysRevA.87.062115</a>

Result language

angličtina

Original language name

Witnessing negativity of Wigner function by estimating fidelities of catlike states from homodyne measurements

Original language description

We derive sampling functions for estimation of quantum-state fidelity with Schrodinger-cat-like states, which are defined as superpositions of two coherent states with opposite amplitudes. We also provide sampling functions for fidelity with squeezed Fock states that can approximate the catlike states and can be generated from Gaussian squeezed states by conditional photon subtraction. The fidelities can be determined by averaging the sampling functions over quadrature statistics measured by homodyne detection. The sampling functions are designed such that they can compensate for losses and inefficient homodyning provided that the overall efficiency exceeds a certain threshold. The fidelity with an odd coherent state and the fidelity with a squeezed odd Fock state provide convenient witnesses of negativity of the Wigner function of the measured state. The negativity of the Wigner function at the origin of phase space is certified if any of these fidelities exceeds 0.5. Finally, we disc

Czech name

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Czech description

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Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

BH - Optics, masers and lasers

OECD FORD branch

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Project

<a href="/en/project/GAP205%2F12%2F0577" target="_blank" >GAP205/12/0577: Reliable highly nonlinear quantum information processing of light</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2013

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Physical Review A

ISSN

1050-2947

e-ISSN

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Volume of the periodical

87

Issue of the periodical within the volume

6

Country of publishing house

US - UNITED STATES

Number of pages

9

Pages from-to

"062115-1"-"062115-9"

UT code for WoS article

000320764300005

EID of the result in the Scopus database

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