Non-ergodic one-magnon magnetization dynamics of the Kagome lattice antiferromagnet
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Henrik Schlüter
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Jannis Eckseler
Abstract
The present view of modern physics on non-equilibrium dynamics is that generic systems equilibrate or thermalize under rather general conditions, even closed systems under unitary time evolution. The investigation of exceptions thus not only appears attractive, in view of quantum computing where thermalization is a threat it also seems to be necessary. Here, we present aspects of the one-magnon dynamics on the Kagome lattice antiferromagnet as an example of a non-equilibrating dynamics due to flat bands. Similar to the one-dimensional delta chain localized eigenstates also called localized magnons lead to disorder-free localization and prevent the system from equilibration.
Funding source: Deutsche Forschungsgemeinschaft
Award Identifier / Grant number: 355031190 (FOR 2692)
Award Identifier / Grant number: 397300368 (SCHN 615/25-2)
Award Identifier / Grant number: 449703145 (SCHN 615/28-1)
Acknowledgments
We would like to thank our collaborator and friend Johannes Richter, who passed away in May 2025, for many insightful discussions. HS likes to thank Katarína Karl’ová for inspiring discussions. This work was supported by the Deutsche Forschungsgemeinschaft DFG (355031190 (FOR 2692); 397300368 (SCHN 615/25-2)) as well as (449703145 (SCHN 615/28-1)).
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Research ethics: Not applicable.
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Informed consent: Not applicable.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared.
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Conflict of interest: The author states no conflict of interest.
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Research funding: This work was supported by the Deutsche Forschungsgemeinschaft DFG (355031190 (FOR 2692); 397300368 (SCHN 615/25-2)) as well as (449703145 (SCHN 615/28-1)).
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Data availability: Not applicable.
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