ADDITIVITY IN ISOTROPIC QUANTUM SPIN CHANNELS
نویسندگان
چکیده
منابع مشابه
Some new additivity results on quantum channels
In this paper we introduce a lemma. This lemma states that for a unitary covariant channel Ψ and a channel M such that M(ρ0) is of rank one for some state ρ0 ∈ S(H) the additivity of the minimal output entropy of Ψ implies that of Ψ ◦M , and the multiplicativity of the maximal output p-norm of Ψ, that of Ψ ◦M . For the product channel of the depolarising channel and an arbitrary channel the add...
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Abstract We show that for the tensor product of an entanglement-breaking quantum channel with an arbitrary quantum channel, both the minimum entropy of an output of the channel and the Holevo-Schumacher-Westmoreland capacity are additive. In addition, for the tensor product of two arbitrary quantum channels, we give a bound involving entanglement of formation for the amount of subadditivity (fo...
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Spin networks are an ideal theoretical playground to devise, test and analyze quantum information processing [1]. Examples are the implementation of computational models in spin chains introduced in Refs. [2, 3] or the possibility to realize approximate quantum cloners [4]. In the context of quantum communication, several protocols have been proposed which would allow distant parties to exchang...
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ژورنال
عنوان ژورنال: International Journal of Quantum Information
سال: 2006
ISSN: 0219-7499,1793-6918
DOI: 10.1142/s0219749906001931