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arXiv · 2202.09624

Maximal coin-walker entanglement in a ballistic quantum walk

Rong Zhang·Ran Yang·Jian Guo·Chang-Wei Sun·Jia-Chen Duan·Heng Zhou·Zhenda Xie·Ping Xu·Yan-Xiao Gong·Shi-Ning Zhu
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Abstract

We report the position-inhomogeneous quantum walk (IQW) can be utilized to produce the maximal high dimensional entanglement while maintaining the quadratic speedup spread of the wave-function. Our calculations show that the maximal coin-walker entanglement can be generated in any odd steps or asymptotically in even steps, and the nearly maximal entanglement can be obtained in even steps after $2$. We implement the IQW by a stable resource-saving time-bin optical network, in which a polarization Sagnac loop is employed to realize the precisely tunable phase shift. Our approach opens up an efficient way for high-dimensional entanglement engineering as well as promotes investigations on the role of coin-walker interactions in QW based applications.

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Rong Zhang, Ran Yang, Jian Guo, Chang-Wei Sun, Jia-Chen Duan, Heng Zhou, Zhenda Xie, Ping Xu, Yan-Xiao Gong, Shi-Ning Zhu. 2022-02-19. Maximal coin-walker entanglement in a ballistic quantum walk. https://doi.org/10.1103/physreva.105.042216

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