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arXiv:2402.00936 · Nature Communications

Enhanced quantum state transfer by circumventing quantum chaotic behavior

Liang Xiang, Jiachen Chen, Zitian Zhu, Zixuan Song, Zehang Bao, Xuhao Zhu, Feitong Jin, Ke Wang, Shibo Xu, Yiren Zou, Hekang Li, Zhen Wang, Chao Song, Alexander Yue, Justine Partridge, Qiujiang Guo, Rubem Mondaini, H. Wang, Richard T. Scalettar

Published Jun 10, 2024• 28 citations

Abstract

The ability to realize high-fidelity quantum communication is one of the many facets required to build generic quantum computing devices. In addition to quantum processing, sensing, and storage, transferring the resulting quantum states demands a careful design that finds no parallel in classical communication. Existing experimental demonstrations of quantum information transfer in solid-state quantum systems are largely confined to small chains with few qubits, often relying upon non-generic schemes. Here, by using a superconducting quantum circuit featuring thirty-six tunable qubits, accompanied by general optimization procedures deeply rooted in overcoming quantum chaotic behavior, we demonstrate a scalable protocol for transferring few-particle quantum states in a two-dimensional quantum network. These include single-qubit excitation, two-qubit entangled states, and two excitations for which many-body effects are present. Our approach, combined with the quantum circuit's versatility, paves the way to short-distance quantum communication for connecting distributed quantum processors or registers, even if hampered by inherent imperfections in actual quantum devices.

DOI: 10.1038/s41467-024-48791-3

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