Quantum copying: Beyond the no-cloning theorem
- 1 September 1996
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review A
- Vol. 54 (3) , 1844-1852
- https://doi.org/10.1103/physreva.54.1844
Abstract
We analyze the possibility of copying (that is, cloning) arbitrary states of a quantum-mechanical spin-1/2 system. We show that there exists a ‘‘universal quantum-copying machine’’ (i.e., transformation) which approximately copies quantum-mechanical states such that the quality of its output does not depend on the input. We also examine a machine which combines a unitary transformation and a selective measurement to produce good copies of states in the neighborhood of a particular state. We discuss the problem of measurement of the output states. © 1996 The American Physical Society.Keywords
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This publication has 7 references indexed in Scilit:
- Noncommuting Mixed States Cannot Be BroadcastPhysical Review Letters, 1996
- Reconstruction of Wigner Functions on Different Observation LevelsAnnals of Physics, 1996
- Quantum codingPhysical Review A, 1995
- Entropy as a measure of quantum optical correlationPhysical Review A, 1989
- A single quantum cannot be clonedNature, 1982
- General properties of entropyReviews of Modern Physics, 1978
- Entropy inequalitiesCommunications in Mathematical Physics, 1970