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arXiv · 2401.13625

Kibble-Zurek mechanism and errors of gapped quantum phases

Amit Jamadagni·Javad Kazemi·Arpan Bhattacharyya
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Abstract

Kibble-Zurek mechanism relates the domain of non-equilibrium dynamics with the critical properties at equilibrium. It establishes a power law connection between non-equilibrium defects quenched through a continuous phase transition and the quench rate via the scaling exponent. We present a novel numerical scheme to estimate the scaling exponent wherein the notion of defects is mapped to errors, previously introduced to quantify a variety of gapped quantum phases. To demonstrate the versatility of our method we conduct numerical experiments across a broad spectrum of spin-half models hosting local and symmetry protected topological order. Furthermore, an implementation of the quench dynamics featuring a topological phase transition on a digital quantum computer is proposed to quantify the associated criticality.

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Amit Jamadagni, Javad Kazemi, Arpan Bhattacharyya. 2024-01-24. Kibble-Zurek mechanism and errors of gapped quantum phases. https://doi.org/10.1103/physrevb.110.045140

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