Direct method for measuring of purity, superfidelity, and subfidelity of photonic two-qubit mixed states

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F13%3A33146337" target="_blank" >RIV/61989592:15310/13:33146337 - isvavai.cz</a>

Výsledek na webu

<a href="http://pra.aps.org/pdf/PRA/v88/i5/e052104" target="_blank" >http://pra.aps.org/pdf/PRA/v88/i5/e052104</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevA.88.052104" target="_blank" >10.1103/PhysRevA.88.052104</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Direct method for measuring of purity, superfidelity, and subfidelity of photonic two-qubit mixed states

Popis výsledku v původním jazyce

The Uhlmann-Jozsa fidelity (or, equivalently, the Bures distance) is a basic concept of quantum communication and quantum information, which however is very difficult to measure efficiently without recourse to quantum tomography. Here we propose a directexperimental method to estimate the fidelity between two unknown two-qubit mixed states via the measurement of the upper and lower bounds of the fidelity, which are referred to as the superfidelity and subfidelity, respectively. Our method enables a direct measurement of the first- and second-order overlaps between two arbitrary two-qubit states. In particular, the method can be applied to measure the purity (or linear entropy) of a single two-qubit mixed state in a direct experiment. We also propose and critically compare several experimental strategies for measuring the sub- and superfidelities of polarization states of photons in various linear-optical setups.

Název v anglickém jazyce

Direct method for measuring of purity, superfidelity, and subfidelity of photonic two-qubit mixed states

Popis výsledku anglicky

The Uhlmann-Jozsa fidelity (or, equivalently, the Bures distance) is a basic concept of quantum communication and quantum information, which however is very difficult to measure efficiently without recourse to quantum tomography. Here we propose a directexperimental method to estimate the fidelity between two unknown two-qubit mixed states via the measurement of the upper and lower bounds of the fidelity, which are referred to as the superfidelity and subfidelity, respectively. Our method enables a direct measurement of the first- and second-order overlaps between two arbitrary two-qubit states. In particular, the method can be applied to measure the purity (or linear entropy) of a single two-qubit mixed state in a direct experiment. We also propose and critically compare several experimental strategies for measuring the sub- and superfidelities of polarization states of photons in various linear-optical setups.

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

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

2013

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

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Svazek periodika

88

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

8

Strana od-do

"052104-1"-"052104-8"

Kód UT WoS článku

000326815800001

EID výsledku v databázi Scopus

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