Interferometric detection of Chern numbers in topological optical lattices

TL;DR

This paper proposes an interferometric method to directly measure Chern numbers in topological optical lattices by detecting the Zak phase, enabling experimental identification of topological phases.

Contribution

It introduces a practical interferometric approach to measure Chern numbers via Zak phase detection, applicable to various topological systems.

Findings

Can distinguish Zak phases of ±2π from 0 in the Brillouin zone

Feasible under realistic experimental conditions

Applicable to high Chern number systems

Abstract

Topological states of matter emergent as a new type of quantum phases, which can be distinguished by their associated topological invariants, e.g., Chern numbers. Currently, there is increasing in-terests toward the physically detection of the new predicted topological phases. Here, we propose an interferometric approach to directly measure the Chern number in a topological optical lattice via detecting the associated Zak phase. We show that this interferometric approach can distinguish Zak phases of plus or minus 2{\pi} from 0 in the first Brillouin zone, and thus provides a new tool to directly detect the Chern number of topological systems. In addition, we demonstrate that this method is feasible under realistic experimental conditions and widely applicable for many systems. Finally, this scheme can be readily generalized to detect high Chern number systems.