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arXiv · 2506.12005

Robustness of Floquet topological phase at room temperature: a first-principles dynamics study

Ruiyi Zhou·Yosuke Kanai
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Abstract

Nonadiabatic Thouless pumping of electrons is studied within the framework of topological Floquet engineering, particularly focused on how atomic lattice dynamics affect the emergent Floquet topological phase in trans-polyacetylene under the driving electric field. As similarly done in the earlier work [Zhou and Kanai, J. Phys. Chem. Lett., 12, 4496 (2021)], the real-time time-dependent density functional theory and Ehrenfest dynamics simulations were used to investigate the extent to which the number of pumped charges remains equal to the topological invariant, the winding number, when the temperature effect of ions and the dynamical coupling of electrons and ions are taken into account. Our theoretical work shows that the Floquet topological phase remains intact but the condition on the driving field necessary for observing the topological phase becomes more limiting.

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Ruiyi Zhou, Yosuke Kanai. 2025-06-13. Robustness of Floquet topological phase at room temperature: a first-principles dynamics study. https://arxiv.org/abs/2506.12005

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