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arXiv · 1607.00082

Hyperentanglement purification for two-photon six-qubit quantum systems

Guan-Yu Wang·Qian Liu·Fu-Guo Deng
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Abstract

Recently, two-photon six-qubit hyperentangled states were produced in experiment and they can improve the channel capacity of quantum communication largely. Here we present a scheme for the hyperentanglement purification of nonlocal two-photon systems in three degrees of freedom (DOFs), including the polarization, the first-longitudinal-momentum, and the second longitudinal momentum DOFs. Our hyperentanglement purification protocol (hyper-EPP) is constructed with two steps resorting to parity-check quantum nondemolition measurement on the three DOFs and SWAP gates, respectively. With these two steps, the bit-flip errors in the three DOFs can be corrected efficiently. Also, we show that using SWAP gates is a universal method for hyper-EPP in the polarization DOF and multiple longitudinal momentum DOFs. The implementation of our hyper-EPP is assisted by nitrogen-vacancy centers in optical microcavities, which could be achieved with current techniques. It is useful for long-distance high-capacity quantum communication with two-photon six-qubit hyperentanglement.

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Guan-Yu Wang, Qian Liu, Fu-Guo Deng. 2016-07-01. Hyperentanglement purification for two-photon six-qubit quantum systems. https://doi.org/10.1103/physreva.94.032319

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