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Entanglement purification for high dimensional multipartite systems

Yong Wook Cheong·Seung-Woo Lee·Jinhyoung Lee·Hai-Woong Lee
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Abstract

We propose an entanglement purification protocol for high-dimensional multipartite systems. In the protocol we can select a subensemble in a pure generalized Greenberger-Horne-Zeilinger (GHZ) state. This post-selection can be made by detecting the noise which contaminated the initial pure ensemble when the systems past through a noisy environment. For the detection of noise we investigate correlation properties of GHZ states and analyze their possible errors due to a noisy environment. We show that the presented protocol is more efficient than a simple generalization of the purification protocol for a bipartite state in high dimensions.

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Yong Wook Cheong, Seung-Woo Lee, Jinhyoung Lee, Hai-Woong Lee. 2007-08-10. Entanglement purification for high dimensional multipartite systems. https://arxiv.org/abs/quant-ph/0512173

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