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arXiv · 1112.3141

Necessary and sufficient conditions for local creation of quantum correlation

Xueyuan Hu·Heng Fan·D. L. Zhou·Wu-Ming Liu
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Abstract

Quantum correlation can be created by a local operation from some initially classical states. We prove that the necessary and sufficient condition for a local trace-preserving channel to create quantum correlation is that it is not a commutativity-preserving channel. This condition is valid for arbitrary finite dimension systems. We also derive the explicit form of commutativity-preserving channels. For a qubit, a commutativity-preserving channel is either a completely decohering channel or a mixing channel. For a three-dimensional system (qutrit), a commutativity-preserving channel is either a completely decohering channel or an isotropic channel.

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Xueyuan Hu, Heng Fan, D. L. Zhou, Wu-Ming Liu. 2012-03-07. Necessary and sufficient conditions for local creation of quantum correlation. https://doi.org/10.1103/physreva.85.032102

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