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arXiv · 0806.4788

Generation of Narrow-Band Polarization-Entangled Photon Pairs for Atomic Quantum Memories

Xiao-Hui Bao·Yong Qian·Jian Yang·Han Zhang·Zeng-Bing Chen·Tao Yang·Jian-Wei Pan
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Abstract

We report an experimental realization of a narrow-band polarization-entangled photon source with a linewidth of 9.6 MHz through cavity-enhanced spontaneous parametric down-conversion. This linewidth is comparable to the typical linewidth of atomic ensemble based quantum memories. Single-mode output is realized by setting a reasonable cavity length difference between different polarizations, using of temperature controlled etalons and actively stabilizing the cavity. The entangled property is characterized with quantum state tomography, giving a fidelity of 94% between our state and a maximally entangled state. The coherence length is directly measured to be 32 m through two-photon interference.

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Xiao-Hui Bao, Yong Qian, Jian Yang, Han Zhang, Zeng-Bing Chen, Tao Yang, Jian-Wei Pan. 2008-11-03. Generation of Narrow-Band Polarization-Entangled Photon Pairs for Atomic Quantum Memories. https://doi.org/10.1103/physrevlett.101.190501

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