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arXiv · 2506.12138

Adiabatic echo protocols for robust quantum many-body state preparation

Abstract

Entangled many-body states are a key resource for quantum technologies. Yet their preparation through analog control of interacting quantum systems is often hindered by experimental imperfections. Here, we introduce the adiabatic echo protocol, a general approach to state preparation designed to suppress the effect of static perturbations. We provide an analytical understanding of its robustness in terms of dynamically engineered destructive interference. By applying quantum optimal control methods, we demonstrate that such a protocol emerges naturally in a variety of settings, without requiring assumptions on the form of the control fields. Examples include Greenberger-Horne-Zeilinger state preparation in Ising spin chains and two-dimensional Rydberg atom arrays, as well as the generation of quantum spin liquid states in frustrated Rydberg lattices. Our results highlight the broad applicability of this protocol, providing a practical framework for reliable many-body state preparation in present-day quantum platforms.

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Zhongda Zeng, Giuliano Giudici, Aruku Senoo, Alexander Baumgärtner, Adam M. Kaufman, Hannes Pichler. 2025-06-13. Adiabatic echo protocols for robust quantum many-body state preparation. https://doi.org/10.1103/z2tj-cwzb

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