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  • Open Access

False Vacuum Decay in Flat-Band Ferromagnets: Role of Quantum Geometry and Chiral Edge States

Fabian Pichler1,2,*, Clemens Kuhlenkamp3,*, and Michael Knap1,2

  • *These authors contributed equally to this work.
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Phys. Rev. Lett. 136, 156502 – Published 15 April, 2026

DOI: https://doi.org/10.1103/q7ss-pvcq

Abstract

Dynamical control of quantum matter is a challenging, yet promising direction for probing strongly correlated states. Motivated by recent experiments in twisted MoTe2 that demonstrated optical control of magnetization, we propose a protocol for probing magnetization dynamics in flat-band ferromagnets. We investigate the nucleation and dynamical growth of magnetic bubbles prepared on top of a false vaccum in both itinerant ferromagnets and spin-polarized Chern insulators. For ferromagnetic metals, we emphasize the crucial role of a nontrivial quantum geometry in the magnetization dynamics, which in turn also provides a probe for the quantum metric. Furthermore, for quantum Hall ferromagnets, we show how properties of chiral edge modes localized at domain-wall boundaries can be dynamically accessed. Our Letter demonstrates the potential for nonequilibrium protocols to control and probe strongly correlated phases, with particular relevance for twisted MoTe2 and graphene-based flat-band ferromagnets.

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Phys. Rev. Lett. 136, 156502– Published 15 April, 2026
  • Received 15 December 2025
  • Accepted 27 March 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

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