Separability of Very Noisy Mixed States and Implications for NMR Quantum Computing
نویسندگان
چکیده
S. L. Braunstein,1 C. M. Caves,2 R. Jozsa,3 N. Linden,4 S. Popescu,4,5 and R. Schack2,6 1SEECS, University of Wales, Bangor LL57 1UT, United Kingdom 2Center for Advanced Studies, Department of Physics and Astronomy, University of New Mexico, Albuquerque, New Mexico 87131-1156 3School of Mathematics and Statistics, University of Plymouth, Devon PL4 8AA, United Kingdom 4Isaac Newton Institute for Mathematical Sciences, Cambridge CB3 0EH, United Kingdom 5BRIMS, Hewlett-Packard Laboratories, Stoke Gifford, Bristol BS12 6QZ, United Kingdom 6Department of Mathematics, Royal Holloway, University of London, Egham, Surrey TW20 0EX, United Kingdom (Received 23 November 1998)
منابع مشابه
2 00 4 New considerations on the separability of very noisy mixed states and implications for NMR quantum computing
We revise the problem first addressed by Braunstein and co-workers (Phys. Rev. Lett. 83 (5) (1999) 1054) concerning the separability of very noisy mixed states represented by general density matrices with the form ρ ǫ = (1−ǫ)M d +ǫρ 1. From a detailed numerical analysis, it is shown that: (1) there exist infinite values in the interval taken for the density matrix expansion coefficients, −1 ≤ c...
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