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arXiv · 0811.2270

Robust quantum repeater with atomic ensembles and single-photon sources

Fang-Yu Hong·Shi-Jie Xiong
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Abstract

We present a quantum repeater protocol using atomic ensembles, linear optics and single-photon sources. Two local 'polarization' entangled states of atomic ensembles $u$ and $d$ are generated by absorbing a single photon emitted by an on-demand single-photon sources, based on which high-fidelity local entanglement between four ensembles can be established efficiently through Bell-state measurement. Entanglement in basic links and entanglement connection between links are carried out by the use of two-photon interference. In addition to being robust against phase fluctuations in the quantum channels, this scheme may speed up quantum communication with higher fidelity by about 2 orders of magnitude for 1280 km compared with the partial read (PR) protocol (Sangouard {\it et al.}, Phys. Rev. A {\bf77}, 062301 (2008)) which may generate entanglement most quickly among the previous schemes with the same ingredients.

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Fang-Yu Hong, Shi-Jie Xiong. 2008-11-14. Robust quantum repeater with atomic ensembles and single-photon sources. https://doi.org/10.1103/physreva.79.052341

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