Nonclassical correlations in continuous-variable non-Gaussian Werner states

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F12%3A33140113" target="_blank" >RIV/61989592:15310/12:33140113 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1103/PhysRevA.85.022326" target="_blank" >http://dx.doi.org/10.1103/PhysRevA.85.022326</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevA.85.022326" target="_blank" >10.1103/PhysRevA.85.022326</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Nonclassical correlations in continuous-variable non-Gaussian Werner states

Popis výsledku v původním jazyce

We study nonclassical correlations beyond entanglement in a family of two-mode non-Gaussian states which represent the continuous-variable counterpart of two-qubit Werner states. We evaluate quantum discord and other quantumness measures obtaining exactanalytical results in special instances, and upper and lower bounds in the general case. Non-Gaussian measurements such as photon counting are in general necessary to solve the optimization in the definition of quantum discord, whereas Gaussian measurements are strictly suboptimal for the considered states. The gap between Gaussian and optimal non-Gaussian conditional entropy is found to be proportional to a measure of non-Gaussianity in the regime of low squeezing, for a subclass of continuous-variableWerner states. We further study an example of a non-Gaussian state which is positive under partial transposition, and whose nonclassical correlations stay finite and small even for infinite squeezing. Our results pave the way to a system

Název v anglickém jazyce

Nonclassical correlations in continuous-variable non-Gaussian Werner states

Popis výsledku anglicky

We study nonclassical correlations beyond entanglement in a family of two-mode non-Gaussian states which represent the continuous-variable counterpart of two-qubit Werner states. We evaluate quantum discord and other quantumness measures obtaining exactanalytical results in special instances, and upper and lower bounds in the general case. Non-Gaussian measurements such as photon counting are in general necessary to solve the optimization in the definition of quantum discord, whereas Gaussian measurements are strictly suboptimal for the considered states. The gap between Gaussian and optimal non-Gaussian conditional entropy is found to be proportional to a measure of non-Gaussianity in the regime of low squeezing, for a subclass of continuous-variableWerner states. We further study an example of a non-Gaussian state which is positive under partial transposition, and whose nonclassical correlations stay finite and small even for infinite squeezing. Our results pave the way to a system

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BH - Optika, masery a lasery

OECD FORD obor

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Projekt

<a href="/cs/project/LC06007" target="_blank" >LC06007: Centrum moderní optiky</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2012

Kód důvěrnosti údajů

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

Název periodika

Physical Review A

ISSN

1050-2947

e-ISSN

—

Svazek periodika

85

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

12

Strana od-do

"022326-1"-"022326-12"

Kód UT WoS článku

000300564500007

EID výsledku v databázi Scopus

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