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

TL;DR

This study investigates how atomic lattice dynamics influence the stability of Floquet topological phases in trans-polyacetylene at room temperature, revealing that the phase remains robust but requires more precise driving conditions.

Contribution

It provides a first-principles real-time simulation demonstrating the robustness of Floquet topological phases under realistic thermal and dynamical conditions.

Findings

Floquet topological phase remains intact at room temperature.

Driving field conditions become more restrictive due to lattice dynamics.

Topological invariant (winding number) is preserved despite thermal effects.

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.