Full investigation of nonadiabatic dynamical characterization in arbitrary quenching process

TL;DR

This paper thoroughly investigates nonadiabatic slow quench dynamics in a 2D Chern insulator, demonstrating that both initial and final topological phases can be characterized via time-averaged spin polarization, extending prior understanding.

Contribution

It introduces a comprehensive analysis of various quenching processes, showing that topological invariants can be dynamically characterized during slow quenches, not just at the final state.

Findings

Both initial and final topological phases can be characterized.

Time-averaged spin polarization captures topological invariants.

Distinct processes can be identified by regions where spin polarization vanishes.

Abstract

Recently, dynamical characterization of bulk topology has been experimentally realized under nonadiabatic sudden quench dynamics. However, it has been shown that only the topology of final phase can be characterized when the system is quenched from initial topologically trivial phase. In this paper, taking the two-dimensional Chern insulator as an example, we make a thorough investigation of different types of quenching processes under nonadiabatic slow quench dynamics, and study not only the processes between nontrivial phase and trivial phase, but also between the phases with different topological invariants. We find that, under slow quench dynamics, both the initial and final topological phase can be characterized and the topological invariant can be captured by time-averaged spin polarization. Moreover, different types of processes can be distinguished from the special regions where the time-averaged spin polarization vanishes. All the dynamical characterization schemes are entirely based on the experimentally measurable quantity time-averaged spin polarization, and thus one can expect our findings may provide reference for future experiments.