Experimental reconstruction of the Berry curvature in a topological Bloch band

TL;DR

This paper demonstrates a method to experimentally measure the Berry curvature across the entire momentum space in topological bands using ultracold atoms, advancing the understanding of topological phases.

Contribution

It introduces a technique for full momentum-resolved measurement of Berry curvature in topological bands with ultracold atoms, enabling exploration of complex topological phases.

Findings

Successful measurement of Berry curvature distribution

Validation of topological band generation via resonant driving

Potential for studying interacting topological phases

Abstract

Topological properties lie at the heart of many fascinating phenomena in solid state systems such as quantum Hall systems or Chern insulators. The topology can be captured by the distribution of Berry curvature, which describes the geometry of the eigenstates across the Brillouin zone. Employing fermionic ultracold atoms in a hexagonal optical lattice, we generate topological bands using resonant driving and show a full momentum-resolved measurement of the ensuing Berry curvature. Our results pave the way to explore intriguing phases of matter with interactions in topological band structures.