Priority Choice Experimental Two-Qubit Tomography: Measuring One by One All Elements of Density Matrices

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F16%3A33158912" target="_blank" >RIV/61989592:15310/16:33158912 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68378271:_____/16:00463819

Výsledek na webu

<a href="http://file:///D:/dokumenty/Downloads/srep19610.pdf" target="_blank" >http://file:///D:/dokumenty/Downloads/srep19610.pdf</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1038/srep19610" target="_blank" >10.1038/srep19610</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Priority Choice Experimental Two-Qubit Tomography: Measuring One by One All Elements of Density Matrices

Popis výsledku v původním jazyce

In standard optical tomographic methods, the off-diagonal elements of a density matrix. are measured indirectly. Thus, the reconstruction of., even if it is based on linear inversion, typically magnifies small errors in the experimental data. Recently, an optimal tomography solution measuring all the elements of. one-by-one without error magnification has been theoretically proposed. We implemented this method for two-qubit polarization states. For comparison, we also experimentally implemented other well-known tomographic protocols, either based solely on local measurements (of, e.g., the Pauli operators and James-Kwiat-Munro-White projectors) or with mutually unbiased bases requiring both local and global measurements. We reconstructed seventeen separable, partially and maximally entangled two-qubit polarization states. Our experiments show that our method has the highest stability against errors in comparison to other quantum tomographies. In particular, we demonstrate that each optimally-reconstructed state is embedded in an uncertainty circle of the smallest radius, both in terms of trace distance and disturbance. We explain how to experimentally estimate uncertainty radii for all the implemented tomographies and show that, for each reconstructed state, the relevant uncertainty circles intersect indicating the approximate location of the corresponding physical density matrix.

Název v anglickém jazyce

Priority Choice Experimental Two-Qubit Tomography: Measuring One by One All Elements of Density Matrices

Popis výsledku anglicky

In standard optical tomographic methods, the off-diagonal elements of a density matrix. are measured indirectly. Thus, the reconstruction of., even if it is based on linear inversion, typically magnifies small errors in the experimental data. Recently, an optimal tomography solution measuring all the elements of. one-by-one without error magnification has been theoretically proposed. We implemented this method for two-qubit polarization states. For comparison, we also experimentally implemented other well-known tomographic protocols, either based solely on local measurements (of, e.g., the Pauli operators and James-Kwiat-Munro-White projectors) or with mutually unbiased bases requiring both local and global measurements. We reconstructed seventeen separable, partially and maximally entangled two-qubit polarization states. Our experiments show that our method has the highest stability against errors in comparison to other quantum tomographies. In particular, we demonstrate that each optimally-reconstructed state is embedded in an uncertainty circle of the smallest radius, both in terms of trace distance and disturbance. We explain how to experimentally estimate uncertainty radii for all the implemented tomographies and show that, for each reconstructed state, the relevant uncertainty circles intersect indicating the approximate location of the corresponding physical density matrix.

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

2016

Kód důvěrnosti údajů

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

Název periodika

Scientific Reports

ISSN

2045-2322

e-ISSN

—

Svazek periodika

6

Číslo periodika v rámci svazku

19610

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

7

Strana od-do

"19610-1"-"19610-7"

Kód UT WoS článku

000368768200001

EID výsledku v databázi Scopus

2-s2.0-84955558646