Chefles, Anthony and Barnett, Stephen M. (1999) Strategies and networks for state-dependent quantum cloning. Physical Review A, 60 (1). pp. 136-144. ISSN 1094-1622Full text not available in this repository. (Request a copy from the Strathclyde author)
State-dependent cloning machines that have so far been considered either deterministically copy a set of states approximately or probablistically copy them exactly. In considering the case of two equiprobable pure states, we derive the maximum global fidelity of N approximate clones given M initial exact copies, where N>M. We also consider strategies that interpolate between approximate and exact cloning. A tight inequality is obtained that expresses a trade-off between the global fidelity and success probability. This inequality is found to tend, in the limit N → ∞, to a known inequality that expresses the trade-off between error and inconclusive result probabilities for state-discrimination measurements. Quantum-computational networks are also constructed for the kinds of cloning machine we describe. For this purpose, we introduce two gates: the distinguishability transfer and state separation gates. Their key properties are described and we show how they may be decomposed into basic operations.
|Keywords:||quantum cloning, quantum physics, optics, Optics. Light, Atomic and Molecular Physics, and Optics|
|Subjects:||Science > Physics > Optics. Light|
Faculty of Science > Physics
|Depositing user:||Miss Darcy Spiller|
|Date Deposited:||30 Apr 2008|
|Last modified:||06 Jan 2017 03:56|