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arXiv · 2011.01643

Entangled state generation via quantum walks with multiple coins

Abstract

Generation of entangled state is of paramount importance both from quantum theoretical foundation and technology applications. Entanglement swapping provides an efficient method to generate entanglement in quantum communication protocols. However, perfect Bell measurements for qudits, the key to entanglement swapping, have been proven impossible to achieve by using only linear elements and particle detectors. To avoid this bottleneck, we propose a novel scheme to generate entangled state including two-qubit entangled state, two-qudit entangled state, three-qubit GHZ state and three-qudit GHZ state between several designate parties via the model of quantum walks with multiple coins. Then we conduct experimental realization of Bell state and three-qubit GHZ state between several designate parties on IBM quantum platform and the result has high fidelity by preforming quantum tomography. In the end, we give a practical application of our scheme in multiparty quantum secret sharing.

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Meng Li, Yun Shang. 2020-11-03. Entangled state generation via quantum walks with multiple coins. https://arxiv.org/abs/2011.01643

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