Bell nonlocality and fully entangled fraction measured in an entanglement-swapping device without quantum state tomography

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F17%3A73580743" target="_blank" >RIV/61989592:15310/17:73580743 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68378271:_____/17:00478698

Výsledek na webu

<a href="https://journals.aps.org/pra/pdf/10.1103/PhysRevA.95.030102" target="_blank" >https://journals.aps.org/pra/pdf/10.1103/PhysRevA.95.030102</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevA.95.030102" target="_blank" >10.1103/PhysRevA.95.030102</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Bell nonlocality and fully entangled fraction measured in an entanglement-swapping device without quantum state tomography

Popis výsledku v původním jazyce

We propose and experimentally implement an efficient procedure based on entanglement swapping to determine the Bell nonlocality measure ofHorodecki et al. [Phys. Lett. A200, 340 (1995)] and the fully entangled fraction of Bennett et al. [Phys. Rev. A54, 3824 (1996)] of an arbitrary two-qubit polarization-encoded state. The nonlocality measure corresponds to the amount of the violation of the Clauser-Horne-Shimony-Holt (CHSH) optimized over all measurement settings. By using simultaneously two copies of a given state, we measure directly only six parameters. This is an experimental determination of these quantities without quantum state tomography or continuous monitoring of all measurement bases in the usual CHSH inequality tests. We analyze how well the measured degrees of Bell nonlocality and other entanglement witnesses (including the fully entangled fraction and a nonlinear entropic witness) of an arbitrary two-qubit state can estimate its entanglement. In particular, we measure these witnesses and estimate the negativity of various two-qubit Werner states. Our approach could especially be useful for quantum communication protocols based on entanglement swapping.

Název v anglickém jazyce

Bell nonlocality and fully entangled fraction measured in an entanglement-swapping device without quantum state tomography

Popis výsledku anglicky

We propose and experimentally implement an efficient procedure based on entanglement swapping to determine the Bell nonlocality measure ofHorodecki et al. [Phys. Lett. A200, 340 (1995)] and the fully entangled fraction of Bennett et al. [Phys. Rev. A54, 3824 (1996)] of an arbitrary two-qubit polarization-encoded state. The nonlocality measure corresponds to the amount of the violation of the Clauser-Horne-Shimony-Holt (CHSH) optimized over all measurement settings. By using simultaneously two copies of a given state, we measure directly only six parameters. This is an experimental determination of these quantities without quantum state tomography or continuous monitoring of all measurement bases in the usual CHSH inequality tests. We analyze how well the measured degrees of Bell nonlocality and other entanglement witnesses (including the fully entangled fraction and a nonlinear entropic witness) of an arbitrary two-qubit state can estimate its entanglement. In particular, we measure these witnesses and estimate the negativity of various two-qubit Werner states. Our approach could especially be useful for quantum communication protocols based on entanglement swapping.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10306 - Optics (including laser optics and quantum optics)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

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

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Physical Review A

ISSN

2469-9926

e-ISSN

—

Svazek periodika

95

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

7

Strana od-do

"030102-1"-"030102-7"

Kód UT WoS článku

000395984700001

EID výsledku v databázi Scopus

2-s2.0-85015612523