Purity and state fidelity of quantum channels
نویسندگان
چکیده
منابع مشابه
Purity and state fidelity of quantum channels
We associate with every quantum channel T acting on a Hilbert space H a pair of Hermitian operators, referred to as “Hamiltonians,” over the symmetric subspace of H^2. The expectation values of these Hamiltonians over symmetric product states give either the purity or the pure-state fidelity of T. This allows us to analytically compute these measures for a wide class of channels, and to identif...
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ژورنال
عنوان ژورنال: Physical Review A
سال: 2004
ISSN: 1050-2947,1094-1622
DOI: 10.1103/physreva.70.012315