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arXiv · 2102.05327

Large-scale GHZ states through topologically protected zero-energy mode in a superconducting qutrit-resonator chain

Jin-Xuan Han·Jin-Lei Wu·Yan Wang·Yan Xia·Yong-Yuan Jiang·Jie Song
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Abstract

We propose a superconducting qutrit-resonator chain model, and analytically work out forms of its topological edge states. The existence of the zero-energy mode enables to generate a state transfer between two ends of the chain, accompanied with state flips of all intermediate qutrits, based on which $N$-body Greenberger-Horne-Zeilinger (GHZ) states can be generated with great robustness against disorders of coupling strengths. Three schemes of generating large-scale GHZ states are designed, each of which possesses the robustness against loss of qutrits or of resonators, meeting a certain performance requirement of different experimental devices. With experimentally feasible qutrit-resonator coupling strengths and available coherence times of qutrits and resonators, it has a potential to generate large-scale GHZ states among dozens of qutrits with a high fidelity. Further, we show the experimental consideration of generating GHZ states based on the circuit QED system, and discuss the prospect of realizing fast GHZ states.

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Jin-Xuan Han, Jin-Lei Wu, Yan Wang, Yan Xia, Yong-Yuan Jiang, Jie Song. 2021-02-10. Large-scale GHZ states through topologically protected zero-energy mode in a superconducting qutrit-resonator chain. https://doi.org/10.1103/physreva.103.032402

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