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arXiv · 2501.04460

Experimental demonstration of entanglement pumping with bosonic logical qubits

Jie Zhou·Chuanlong Ma·Yifang Xu·Weizhou Cai·Hongwei Huang·Lida Sun·Guangming Xue·Ziyue Hua·Haifeng Yu·Weiting Wang·Chang-Ling Zou·Luyan Sun
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Abstract

Entanglement is crucial for quantum networks and computation, yet maintaining high-fidelity entangled quantum states is hindered by decoherence and resource-intensive purification methods. Here, we experimentally demonstrate entanglement pumping, utilizing bosonic quantum error correction (QEC) codes as long-coherence-time storage qubits. By repetitively generating entanglement with short-coherence-time qubits and injecting it into error-detectable logical qubits, our approach effectively preserves entanglement. Through error-detection to discard error states and entanglement pumping to mitigate errors within the code space, we extend the existence time of entanglement by nearly 50% compared to the case without entanglement pumping. This entanglement pumping scheme can additionally serve as an erasure detection protocol for the dual-rail code. This work highlights the potential of bosonic logical qubits for scalable quantum networks and introduces a novel paradigm for efficient entanglement management.

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Jie Zhou, Chuanlong Ma, Yifang Xu, Weizhou Cai, Hongwei Huang, Lida Sun, Guangming Xue, Ziyue Hua, Haifeng Yu, Weiting Wang, Chang-Ling Zou, Luyan Sun. 2025-01-08. Experimental demonstration of entanglement pumping with bosonic logical qubits. https://doi.org/10.1103/l43p-py55

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