Observation of a disordered bosonic insulator from weak to strong interactions

Chiara D Errico 1, 2 Eleonora Lucioni 1, 2 Luca Tanzi 1 Lorenzo Gori 1 Guillaume Roux 3 Ian P. McCulloch 4 Thierry Giamarchi 5 Massimo Inguscio 1, 6 Giovanni Modugno 1, 2

Physical Review Letters, American Physical Society, 2014, 113, pp.095301

We employ ultracold atoms with controllable disorder and interaction to study the paradigmatic problem of disordered bosons in the full disorder-interaction plane. Combining measurements of coherence, transport and excitation spectra, we get evidence of an insulating regime extending from weak to strong interaction and surrounding a superfluid-like regime, in general agreement with the theory. For strong interaction, we reveal the presence of a strongly-correlated Bose glass coexisting with a Mott insulator.

  • 1. European Laboratory for Non-linear Spectroscopy (LENS)
  • 2. Istituto Nazionale di Ottica
  • 3. LPTMS - Laboratoire de Physique Théorique et Modèles Statistiques
  • 4. Centre for Engineered Quantum Systems
  • 5. DPMC - Département de Physique de la Matière Condensée
  • 6. INRIM