On Weyl channels being covariant with respect to the maximum commutative group of unitaries
نویسنده
چکیده
We investigate the Weyl channels being covariant with respect to the maximum commutative group of unitary operators. This class includes the quantum depolarizing channel and the ”two-Pauli” channel as well. Then, we show that our estimation of the output entropy for a tensor product of the phase damping channel and the identity channel based upon the decreasing property of the relative entropy allows to prove the additivity conjecture for the minimal output entropy for the quantum depolarizing channel in any prime dimesnsion and for the ”two Pauli” channel in the qubit case.
منابع مشابه
On estimation of the entropy infimum for the output of the Weyl channels being covariant with respect to the maximum commutative group of unitaries
We estimate the von Neumann entropy infimum for the output of the Weyl channels being covariant with respect to the maximum commutative group. In qubit case, such the class includes the quantum depolarizing channel and the ”two-Pauli” channel as well. For the dimesion d = 2 our approach allows to prove the additivity conjecture for the Holevo-Schumacher-Westmoreland bound. Our method is based u...
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