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arXiv · 1408.0048

Two-step hyperentanglement purification with the quantum-state-joining method

Bao-Cang Ren·Fang-Fang Du·Fu-Guo Deng
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Abstract

Hyperentanglement is a promising resource in quantum information processing, especially for increasing the channel capacity of long-distance quantum communication. Hyperentanglement purification is an important method to obtain high-fidelity nonlocal hyperentangled states from mixed hyperentangled states in a long-distance quantum communication process with noisy channels. Here, we present a two-step hyperentanglement purification protocol for nonlocal mixed hyperentangled states with polarization bit-flip errors and spatial-mode phase-flip errors, resorting to polarization-spatial phase-check quantum nondemolition detectors and the quantum-state-joining method (QSJM). With QSJM, the protocol can preserve the states that are discarded in the previous hyperentanglement purification protocols. It has the advantage of a high efficiency, and it is useful for improving the entanglement of photon systems with several degrees of freedom in long-distance high-capacity quantum communication.

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Bao-Cang Ren, Fang-Fang Du, Fu-Guo Deng. 2014-11-10. Two-step hyperentanglement purification with the quantum-state-joining method. https://doi.org/10.1103/physreva.90.052309

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