Quantum disentanglers

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14330%2F00%3A00002895" target="_blank" >RIV/00216224:14330/00:00002895 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Quantum disentanglers

Popis výsledku v původním jazyce

It is not possible to disentangle a qubit in an unknown state psi > from a set of N-1 ancilla qubits prepared in a specific reference state >. That is, it is not possible to perfectly perform the transformation ( psi ,0,...,0 > + ,psi,...,0 > +...+.0,...,0 psi >) --> ,...,0 > circle times psi >. The question is then how well we can do? We consider a number of different methods of extracting an unknown state from an entangled state formed from that qubit and a set of ancilla qubits in a known state. Measuring the whole system is, as expected, the least effective method. We present various quantum ''devices'' which disentangle the unknown qubit from the set of ancilla qubits. In particular, we present the optimal universal disentangler which disentangles the unknown qubit with a fidelity that does not depend on the state of the qubit, and a probabilistic disentangler which performs the perfect disentangling transformation, but with a probability less than 1.

Název v anglickém jazyce

Quantum disentanglers

Popis výsledku anglicky

It is not possible to disentangle a qubit in an unknown state psi > from a set of N-1 ancilla qubits prepared in a specific reference state >. That is, it is not possible to perfectly perform the transformation ( psi ,0,...,0 > + ,psi,...,0 > +...+.0,...,0 psi >) --> ,...,0 > circle times psi >. The question is then how well we can do? We consider a number of different methods of extracting an unknown state from an entangled state formed from that qubit and a set of ancilla qubits in a known state. Measuring the whole system is, as expected, the least effective method. We present various quantum ''devices'' which disentangle the unknown qubit from the set of ancilla qubits. In particular, we present the optimal universal disentangler which disentangles the unknown qubit with a fidelity that does not depend on the state of the qubit, and a probabilistic disentangler which performs the perfect disentangling transformation, but with a probability less than 1.

Druh

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

CEP obor

BE - Teoretická fyzika

OECD FORD obor

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Projekt

<a href="/cs/project/GA201%2F98%2F0369" target="_blank" >GA201/98/0369: Informatika jako třetí metodologie</a><br>

Návaznosti

Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2000

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

62

Číslo periodika v rámci svazku

05

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

1

Strana od-do

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Kód UT WoS článku

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EID výsledku v databázi Scopus

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