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arXiv · 0705.2549

Optimal discrimination between quantum operations

Lvzhou Li·Daowen Qiu
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Abstract

In this paper, we address the problem of discriminating two given quantum operations. Firstly, based on the Bloch representation of single qubit systems, we give the exact minimum error probability of discriminating two single qubit quantum operations by unentangled input states. In particular, for the Pauli channels discussed in [Phys. Rev. A {\bf 71}, 062340 (2005)], we use a more intuitional and visual method to deal with their discrimination problem. Secondly, we consider the condition for perfect discrimination of two quantum operations. Specially, we get that two generalized Pauli channels are perfectly distinguishable if and only if their characteristic vectors are orthogonal.

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Lvzhou Li, Daowen Qiu. 2007-05-17. Optimal discrimination between quantum operations. https://doi.org/10.1088/1751-8113/41/33/335302

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