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arXiv · 1512.07843

Generalized Kraus operators for the one-qubit depolarizing quantum channel

Momir Arsenijevic·Jasmina Jeknic-Dugic·Miroljub Dugic
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Abstract

Microscopic Hamiltonian models of the composite system "open system + environment" typically do not provide the operator-sum Kraus form of the open system's dynamical map. With the use of a recently de- veloped method [16], we derive the Kraus operators starting from the mi- croscopic Hamiltonian model, i.e. from the proper master equation, of the one-qubit depolarizing channel. Those Kraus operators generalize the stan- dard counterparts, which are widely used in the literature. Comparison of the standard and the here obtained Kraus operators is performed via inves- tigating dynamical change of the Bloch sphere volume, entropy production and the open system's state trace distance. We find that the standard depo- larizing channel is more deteriorating than the generalized one.

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Momir Arsenijevic, Jasmina Jeknic-Dugic, Miroljub Dugic. 2017-04-18. Generalized Kraus operators for the one-qubit depolarizing quantum channel. https://doi.org/10.1007/s13538-017-0502-3

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