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arXiv · 1005.0050

Efficient quantum entanglement distribution over an arbitrary collective-noise channel

Yu-Bo Sheng·Fu-Guo Deng
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Abstract

We present an efficient quantum entanglement distribution over an arbitrary collective-noise channel. The basic idea in the present scheme is that two parties in quantum communication first transmit the entangled states in the frequency degree of freedom which suffers little from the noise in an optical fiber. After the two parties share the photon pairs, they add some operations and equipments to transfer the frequency entanglement of pairs into the polarization entanglement with the success probability of 100\%. Finally, they can get maximally entangled polarization states with polarization independent wavelength division multiplexers and quantum frequency up-conversion which can erase distinguishability for frequency. Compared with conventional entanglement purification protocols, the present scheme works in a deterministic way in principle. Surprisingly, the collective noise leads to an additional advantage.

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Yu-Bo Sheng, Fu-Guo Deng. 2010-05-01. Efficient quantum entanglement distribution over an arbitrary collective-noise channel. https://doi.org/10.1103/physreva.81.042332

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