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arXiv · 2601.21435

Optimized adiabatic-impulse protocol preserving Kibble-Zurek scaling with attenuated anti-Kibble-Zurek behavior

Han-Chuan Kou·Zhi-Han Zhang·Xin-Hui Wu·Yan Zhou·Gang Chen·Peng Li
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Abstract

We propose an optimized adiabatic-impulse (OAI) protocol that substantially reduces the evolution time for crossing a quantum phase transition while preserving Kibble-Zurek (KZ) scaling. Near criticality, the control parameter is ramped linearly across the critical point at a rate characterized by a quench time $\tau_Q$. Away from criticality, the evolution remains adiabatic and is tuned close to the threshold of adiabatic breakdown, as quantified by an adiabatic coefficient $\zeta$ that scales as $\tau_Q^\alpha$. As a consequence, the total evolution time exhibits a sublinear power-law dependence on $\tau_Q$, and the conventional linear quench is recovered in the limit $\alpha\rightarrow\infty$. We apply the OAI protocol to the transverse Ising chain and numerically determine the minimal $\zeta$ required for KZ scaling. We further investigate the nonequilibrium dynamics in the presence of a noisy field that can induce anti-Kibble-Zurek (AKZ) behavior. Within the OAI protocol, noise-induced defects is significantly attenuated due to the shorter evolution time. The optimal quench time at which the defect density is minimized obeys an altered universal power-law scaling with the noise strength. Finally, we generalize the OAI protocol to the nonlinear quenches and numerically demonstrate a marked reduction in noise-induced defects.

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Han-Chuan Kou, Zhi-Han Zhang, Xin-Hui Wu, Yan Zhou, Gang Chen, Peng Li. 2026-01-29. Optimized adiabatic-impulse protocol preserving Kibble-Zurek scaling with attenuated anti-Kibble-Zurek behavior. https://doi.org/10.1103/5xrs-z9ls

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