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arXiv · 2503.22212

Universal Defect Statistics in Counterdiabatic Quantum Critical Dynamics

András Grabarits·Adolfo del Campo
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Abstract

Counterdiabatic driving (CD) provides a framework for suppressing excitations in nonadiabatic processes. Exact CD protocols require nonlocal control fields, and CD approximations with tailored locality are needed for their implementation. However, the performance of local CD schemes remains poorly understood. Here, we develop an analytically tractable local CD expansion scheme and establish a universal scaling theory governing the defect statistics after crossing a quantum phase transition as a function of the CD locality order. Our predictions are tested on the transverse field Ising model and long-range Kitaev models. Our results provide an analytical framework for evaluating the effectiveness of local CD protocols in quantum state preparation, control, and optimization.

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András Grabarits, Adolfo del Campo. 2025-03-28. Universal Defect Statistics in Counterdiabatic Quantum Critical Dynamics. https://arxiv.org/abs/2503.22212

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