Process estimation in the presence of time-invariant memory effects

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14330%2F15%3A00081696" target="_blank" >RIV/00216224:14330/15:00081696 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1103/PhysRevA.92.042315" target="_blank" >http://dx.doi.org/10.1103/PhysRevA.92.042315</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevA.92.042315" target="_blank" >10.1103/PhysRevA.92.042315</a>

Result language

angličtina

Original language name

Process estimation in the presence of time-invariant memory effects

Original language description

Any repeated use of a fixed experimental instrument is subject to memory effects. We design an estimation method uncovering the details of the underlying interaction between the system and the internal memory without having any experimental access to memory degrees of freedom. In such case, by definition, any memoryless quantum process tomography (QPT) fails because the observed data sequences do not satisfy the elementary condition of statistical independence. However, we show that the randomness implemented in certain QPT schemes is sufficient to guarantee the emergence of observable ?statistical? patterns containing complete information on the memory channels. We demonstrate the algorithm in detail for the case of qubit memory channels with two-dimensional memory. Interestingly, we find that for the arbitrary estimation method, the memory channels generated by controlled unitary interactions are indistinguishable from memoryless unitary channels.

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

BE - Theoretical physics

OECD FORD branch

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Project

<a href="/en/project/GAP202%2F12%2F1142" target="_blank" >GAP202/12/1142: Weak Sources of Entanglement and Randomness</a><br>

Continuities

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

Publication year

2015

Confidentiality

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

Name of the periodical

Phys. Rev. A

ISSN

1050-2947

e-ISSN

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Volume of the periodical

92

Issue of the periodical within the volume

4

Country of publishing house

US - UNITED STATES

Number of pages

7

Pages from-to

042315

UT code for WoS article

000362888900002

EID of the result in the Scopus database

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