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arXiv · 2306.16194

Variational generation of spin squeezing on one-dimensional quantum devices with nearest-neighbor interactions

Zheng-Hang Sun·Yong-Yi Wang·Yu-Ran Zhang·Franco Nori·Heng Fan
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Abstract

Efficient preparation of spin-squeezed states is important for quantum-enhanced metrology. Current protocols for generating strong spin squeezing rely on either high dimensionality or long-range interactions. A key challenge is how to generate considerable spin squeezing in one-dimensional systems with only nearest-neighbor interactions. Here, we develop variational spin-squeezing algorithms to solve this problem. We consider both digital and analog quantum circuits for these variational algorithms. After the closed optimization loop of the variational spin-squeezing algorithms, the generated squeezing can be comparable to the strongest squeezing created from two-axis twisting. By analyzing the experimental imperfections, the variational spin-squeezing algorithms proposed in this work are feasible in recent developed noisy intermediate-scale quantum computers.

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Zheng-Hang Sun, Yong-Yi Wang, Yu-Ran Zhang, Franco Nori, Heng Fan. 2023-06-28. Variational generation of spin squeezing on one-dimensional quantum devices with nearest-neighbor interactions. https://doi.org/10.1103/physrevresearch.5.043285

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