Truly local topological dynamics of driven defects in Chern insulator

TL;DR

This paper introduces a local, physically interpretable framework for understanding the dynamics of topological markers in driven defects of Chern insulators, enabling better control and measurement of topological inhomogeneities.

Contribution

It develops a new local equations of motion for topological markers, applicable to interacting systems, and provides a physical response-based perspective on their evolution.

Findings

Markers obey a lattice continuity equation.

The formalism is measurement-friendly and does not rely on single-particle states.

Applicable to interacting topological systems.

Abstract

Robust zero modes supported by defects is one of the key features of topological matter. Its presence renders a system topologically inhomegeneuous, thus having no well-defined global topological invariant. The quantities labeling different areas of the sample according to their topological state were dubbed local topological markers. Here we study their dynamics and the possibility to control their distribution over the sample. We suggest a new perspective on the evolution of local markers. It gives a clear physical description of the markers evolution in terms of response functions and the ease of measurement. Furthermore, new markers' equations of motion are truly local, being ensured that the current of the marker exists and obeys the lattice continuity equation. The formalism presented does not rely on the single-particle quantities therefore might be extended to interacting systems.