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arXiv · 1412.6188

High-dimensional entanglement between distant atomic ensemble memories

Dong-Sheng Ding·Wei Zhang·Shuai Shi·Zhi-Yuan Zhou·Yan Li·Bao-Sen Shi·Guang-Can Guo
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Abstract

Entangled quantum states in high-dimensional space show many advantages compared with entangled states in two-dimensional space. The former enable quantum communication with higher channel capacity, enable more efficient quantum-information processing, and are more feasible for closing the detection loophole in Bell test experiments. Establishing high-dimensional entangled memories is essential for long-distance communication, but its experimental realization is lacking. We experimentally established high-dimensional entanglement in orbital angular momentum space between two atomic ensembles separated by 1 m. We reconstructed the density matrix for a three-dimensional entanglement and obtained an entanglement fidelity of 83.9+/-2.9%. More importantly, we confirmed the successful preparation of a state entangled in more than three-dimensional space (up to seven-dimensional) using entanglement witnesses. Achieving high-dimensional entanglement represents a significant step towards a high-capacity quantum network.

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Dong-Sheng Ding, Wei Zhang, Shuai Shi, Zhi-Yuan Zhou, Yan Li, Bao-Sen Shi, Guang-Can Guo. 2014-12-19. High-dimensional entanglement between distant atomic ensemble memories. https://arxiv.org/abs/1412.6188

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