Detailed Information on Publication Record
2000
Quantum disentanglers
BŮŽEK, Vladimír and M. HILLERYBasic information
Original name
Quantum disentanglers
Authors
BŮŽEK, Vladimír and M. HILLERY
Edition
Physical Review A, USA, American Physical Society, 2000, 1050-2947
Other information
Language
English
Type of outcome
Článek v odborném periodiku
Field of Study
10301 Atomic, molecular and chemical physics
Country of publisher
United States of America
Confidentiality degree
není předmětem státního či obchodního tajemství
Impact factor
Impact factor: 2.831
RIV identification code
RIV/00216224:14330/00:00002895
Organization unit
Faculty of Informatics
Keywords in English
CLONING; STATES; INFORMATION; ENSEMBLES
Tags
Změněno: 21/2/2001 12:27, prof. Dr. phil. Jakub Mácha, Ph.D.
Abstract
V originále
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 \0 >. That is, it is not possible to perfectly perform the transformation (\ psi ,0,...,0 > + \0,psi,...,0 > +...+\0.0,...,0 psi >) --> \0,...,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.
Links
| GA201/98/0369, research and development project |
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| MSM 143300001, plan (intention) |
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