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arXiv · 2404.18646

Permanent oscillations and solitary wave behavior in flatband Heisenberg quantum spin systems

J. Eckseler·J. Schnack
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Abstract

Research on the emergence of thermodynamics in closed quantum systems under unitary time evolution arrived at the consensus that generic systems equilibrate under rather general assumptions. A new focus of the field is thus on exceptions. Persistent oscillations are one possible hallmark of non-ergodic time evolution. While time-crystalline behavior results from, e.g., many-body localization, here we show that ever-revolving solitary waves emerge in flatband Heisenberg quantum spin systems. This phenomenon is rather general for a variety of frustrated spin systems in one, two, and three dimensions as well as for Hubbard systems.

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J. Eckseler, J. Schnack. 2024-04-29. Permanent oscillations and solitary wave behavior in flatband Heisenberg quantum spin systems. https://doi.org/10.1103/physrevresearch.7.013178

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