Many-body slow quench dynamics and nonadiabatic characterization of topological phases

TL;DR

This paper investigates the many-body quench dynamics of topological phases, demonstrating that key topological features can be characterized through a solvable three-level Landau-Zener model and time-averaged spin polarization.

Contribution

It extends the understanding of topological phase characterization from single-particle to many-body systems using an exactly solvable model.

Findings

Many-body quench dynamics can be reduced to a three-level Landau-Zener model.

Time-averaged spin polarization effectively characterizes bulk topology.

The analytical approach provides a basis for experimental comparison.

Abstract

Previous studies have shown that the bulk topology of single-particle systems can be captured by the band inversion surface or by the spin inversion surface emerged on the time-averaged spin polarization. Most of the studies, however, are based on the single-particle picture even though the systems are fermionic and of multi-bands. Here, we study the many-body quench dynamics of topological systems with all the valence bands fully occupied, and show that the concepts of band inversion surface and spin inversion surface are still valid. More importantly, the many-body quench dynamics is shown to be reduced to a nontrivial three-level Landau-Zener model, which can be solved exactly. Based on the analytical results, the topological spin texture revealed by the time-averaged spin polarization can be applied to characterize the bulk topology and thus provides a direct comparison for future experiments.