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Robust transmission of non-Gaussian entanglement over optical fibers

Asoka Biswas·Daniel A. Lidar
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Abstract

We show how the entanglement in a wide range of continuous variable non-Gaussian states can be preserved against decoherence for long-range quantum communication through an optical fiber. We apply protection via decoherence-free subspaces and quantum dynamical decoupling to this end. The latter is implemented by inserting phase shifters at regular intervals $\Delta $ inside the fiber, where $\Delta $ is roughly the ratio of the speed of light in the fiber to the bath high-frequency cutoff. Detailed estimates of relevant parameters are provided using the boson-boson model of system-bath interaction for silica fibers, and $\Delta $ is found to be on the order of a millimeter.

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Asoka Biswas, Daniel A. Lidar. 2006-05-17. Robust transmission of non-Gaussian entanglement over optical fibers. https://doi.org/10.1103/physreva.74.062303

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