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arXiv · 2410.05659

Experimental realization of direct entangling gates between dual-type qubits

Chenxi Wang·Chuanxin Huang·Hongxuan Zhang·Hongyuan Hu·Zhichao Mao·Panyu Hou·Yukai Wu·Zichao Zhou·Luming Duan
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Abstract

Dual-type qubits have become a promising way to suppress the crosstalk error of auxiliary operations in large-scale ion trap quantum computation. Here we demonstrate a direct entangling gate between dual-type qubits encoded in the $S_{1/2}$ and $D_{5/2}$ hyperfine manifolds of $^{137}\mathrm{Ba}^{+}$ ions. Our scheme is economic in the hardware, requiring only a single $532\,$nm laser system to entangle both qubit types by driving their Raman transitions. We achieve a Bell state fidelity of $96.3(4)\%$ for the dual-type Molmer-Sorensen gate between an $S$-$D$ ion pair, comparable to that for the same-type $S$-$S$ or $D$-$D$ gates. This technique can reduce the overhead for back-and-forth conversions between dual-type qubits in the quantum circuit with wide applications in quantum error correction and ion-photon quantum networks.

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Chenxi Wang, Chuanxin Huang, Hongxuan Zhang, Hongyuan Hu, Zhichao Mao, Panyu Hou, Yukai Wu, Zichao Zhou, Luming Duan. 2024-10-08. Experimental realization of direct entangling gates between dual-type qubits. https://doi.org/10.1103/physrevlett.134.010601

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