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arXiv · 2311.04560

Fast Generation of GHZ-like States Using Collective-Spin XYZ Model

Xuanchen Zhang·Zhiyao Hu·Yong-Chun Liu
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Abstract

The Greenberger-Horne-Zeilinger (GHZ) state is a key resource for quantum information processing and quantum metrology. The atomic GHZ state can be generated by one-axis twisting (OAT) interaction $H_{\mathrm{OAT}}=\chi J_{z}^{2}$ with $\chi $ the interaction strength, but it requires a long evolution time $\chi t=\pi /2$ and is thus seriously influenced by decoherence and losses. Here we propose a three-body collective-spin XYZ model which creates a GHZ-like state in a very short timescale $\chi t\sim \ln {N}/N$ for $N$ particles. We show that this model can be effectively produced by applying Floquet driving to an original OAT Hamiltonian. Compared with the ideal GHZ state, the GHZ-like state generated using our model can maintain similar metrological properties reaching the Heisenberg-limited scaling, and it shows better robustness to decoherence and particle losses. This work opens the avenue for generating GHZ-like states with a large particle number, which holds great potential for the study of macroscopic quantum effects and for applications in quantum metrology and quantum information.

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Xuanchen Zhang, Zhiyao Hu, Yong-Chun Liu. 2023-11-08. Fast Generation of GHZ-like States Using Collective-Spin XYZ Model. https://doi.org/10.1103/physrevlett.132.113402

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