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arXiv · 2306.14405

Realization of a crosstalk-avoided quantum network node with dual-type qubits by the same ion species

L. Feng·Y. -Y Huang·Y. -K. Wu·W. -X. Guo·J. -Y. Ma·H. -X. Yang·L. Zhang·Y. Wang·C. -X. Huang·C. Zhang·L. Yao·B. -X. Qi·Y. -F. Pu·Z. -C. Zhou·L. -M. Duan
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Abstract

Generating ion-photon entanglement is a crucial step for scalable trapped-ion quantum networks. To avoid the crosstalk on memory qubits carrying quantum information, it is common to use a different ion species for ion-photon entanglement generation such that the scattered photons are far off-resonant for the memory qubits. However, such a dual-species scheme requires elaborate control of the portion and the location of different ion species, and can be subject to inefficient sympathetic cooling. Here we demonstrate a trapped-ion quantum network node in the dual-type qubit scheme where two types of qubits are encoded in the $S$ and $F$ hyperfine structure levels of ${}^{171}\mathrm{Yb}^+$ ions. We generate ion photon entanglement for the $S$-qubit in a typical timescale of hundreds of milliseconds, and verify its small crosstalk on a nearby $F$-qubit with coherence time above seconds. Our work demonstrates an enabling function of the dual-type qubit scheme for scalable quantum networks.

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L. Feng, Y. -Y Huang, Y. -K. Wu, W. -X. Guo, J. -Y. Ma, H. -X. Yang, L. Zhang, Y. Wang, C. -X. Huang, C. Zhang, L. Yao, B. -X. Qi, Y. -F. Pu, Z. -C. Zhou, L. -M. Duan. 2023-06-26. Realization of a crosstalk-avoided quantum network node with dual-type qubits by the same ion species. https://arxiv.org/abs/2306.14405

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