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arXiv · 1409.5994

When quantum channel preserves product states

Yu Guo·Zhaofang Bai·Shuanping Du·Xiulan Li
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Abstract

Product states are always considered as the states that don't contain quantum correlation. We discuss here when a quantum channel sends the product states to themselves. The exact forms of such channels are proposed. It is shown that such a quantum channel is a local quantum channel, a composition of a local quantum channel and a flip operation, or such that one of the local states is fixed. Both finite- and infinite-dimensional systems are considered.

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Yu Guo, Zhaofang Bai, Shuanping Du, Xiulan Li. 2014-09-21. When quantum channel preserves product states. https://doi.org/10.1016/s0034-4877(14)00025-1

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