Unital quantum operations on the Bloch ball and Bloch region
نویسندگان
چکیده
منابع مشابه
Unital Quantum Operations on the Bloch Ball and Bloch Region
For one qubit systems, we present a short, elementary argument characterizing unital quantum operators in terms of their action on Bloch vectors. We then show how our approach generalizes to multi-qubit systems, obtaining inequalities that govern when a “diagonal” superoperator on the Bloch region is a quantum operator. These inequalities are the n-qubit analogue of the Algoet-Fujiwara conditio...
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ژورنال
عنوان ژورنال: Physical Review A
سال: 2004
ISSN: 1050-2947,1094-1622
DOI: 10.1103/physreva.69.022314