English

Thermodynamics vs. local density fluctuations in the metal/Mott-insulator crossover

Quantum Gases 2016-09-28 v1

Abstract

The crossover between a metal and a Mott insulator leads to a localization of fermions from delocalized Bloch states to localized states. We experimentally study this crossover using fermionic atoms in an optical lattice by measuring thermodynamic and local (on--site) density correlations. In the metallic phase at incommensurable filling we observe the violation of the local fluctuation--dissipation theorem indicating that the thermodynamics cannot be explained by local observables. In contrast, in the Mott-insulator we observe the convergence of local and thermodynamic fluctuations indicating the absence of long--range density-density correlations.

Keywords

Cite

@article{arxiv.1606.04580,
  title  = {Thermodynamics vs. local density fluctuations in the metal/Mott-insulator crossover},
  author = {J. H. Drewes and E. Cocchi and L. A. Miller and C. F. Chan and D. Pertot and F. Brennecke and M. Köhl},
  journal= {arXiv preprint arXiv:1606.04580},
  year   = {2016}
}