Fate of dynamical quantum phase transitions from sudden quench to slow quench limit

Xiang Zhang; Fuxiang Li

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arXiv · 2607.15649

Fate of dynamical quantum phase transitions from sudden quench to slow quench limit

Xiang Zhang·Fuxiang Li

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Abstract

Previous investigations of dynamical quantum phase transition (DQPT) have predominantly focused on sudden quench protocols. In this work, we systematically explore the fate of DQPT from the sudden to the slow quench regime. We establish that DQPT remains robust under slow quenching when the protocol crosses an equilibrium quantum phase transition. Conversely, we show that accidental DQPTs,which occur when the pre and post quench Hamiltonians reside in the same equilibrium phase, can be filtered out in the slow quench limit. This demonstrates that slow quenches can reveal the intrinsic connection between DQPT and equilibrium quantum phase transitions, thereby enabling DQPT to serve as a dynamical probe for identifying equilibrium quantum critical points. We illustrate these findings with examples from the XY chain, the Aubry-Andr\'e model, and the trimer Su-Schrieffer-Heeger model.

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Xiang Zhang, Fuxiang Li. 2026-07-17. Fate of dynamical quantum phase transitions from sudden quench to slow quench limit. https://arxiv.org/abs/2607.15649

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