Experimental Reconstruction of the Berry Curvature in a Floquet Bloch Band

27 May 2016

Photo: AG Sengstock

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 the exploration of intriguing phases of matter with interactions in topological band structures.

Science 352, 1091 (2016)

Press coverage: CUI, UHH

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