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Limitations of practical multi-photon decoherence-free states

Yong-Sheng Zhang·Chuan-Feng Li·Yun-Feng Huang·Guang-Can Guo
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Abstract

It is shown in this paper that decoherence-free subspace (DFS) of practical multi-photon polarization can not avoid the exponential decoherence even in the same extra-environment if the photons are frequency-anticorrelated. The reason lies in that the condition of collective decoherence is not satisfied in this case. As an example, the evolution of biphoton's decoherence-free state is given. Possible solution for feasible multi-photon's DFS state is also given.

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Yong-Sheng Zhang, Chuan-Feng Li, Yun-Feng Huang, Guang-Can Guo. 2005-03-14. Limitations of practical multi-photon decoherence-free states. https://doi.org/10.1103/physreva.72.012308

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