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arXiv · 2507.07875

Preparing spin-squeezed states in Rydberg atom arrays via quantum optimal control

Edison S. Carrera·Harold Erbin·Grégoire Misguich
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Abstract

We present a quantum optimal control protocol to generate highly spin-squeezed states in Rydberg atom arrays coupled via Ising-type van der Waals interactions. Using gradient-based optimization techniques, we construct time-dependent pulse sequences that steer an initial product state toward highly entangled, spin-squeezed states with predefined magnetization and squeezing axes. We focus on the Wineland parameter $\xi_W^2$ to measure spin squeezing, and our approach achieves near-optimal spin squeezing in one-dimensional ring arrays of up to $N=8$ spins, significantly outperforming conventional quench dynamics for all system sizes studied. Remarkably, optimized pulse sequences can be directly scaled to larger arrays without additional optimization, achieving a squeezing parameter as low as $\xi_W^2 = 0.227$ in systems containing $N=50$ spins. This work demonstrates the potential of quantum optimal control methods for preparing highly spin-squeezed states, opening pathways to enhanced quantum metrology.

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Edison S. Carrera, Harold Erbin, Grégoire Misguich. 2025-07-10. Preparing spin-squeezed states in Rydberg atom arrays via quantum optimal control. https://doi.org/10.1103/wdqt-tpwz

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