In June 10th 1999, the Rubidium BEC1 apparatus produced the first italian Bose-Einstein condensate. We soon focused our activity on the study of a quantum gas of 87Rb bosons in optical lattices, investigating static and dynamic properties and enlightening the role of different kinds of instabilities. The last part of the activity was concentrated on the study of the superfluid to Mott insulator transition (also adding disorder and “quasi-disorder”) and on the physics of low-dimensional bosonic gases, characterized by measuring the excitation spectrum of these systems through inelastic light scattering. The BEC1 experiment retired in 2014 after 15 years of activity. We would like to thank all the people – students, technicians, and researchers – who have contributed to these exciting fifteen years of activity.

Breaking the order of a Mott insulator

We use a two-color lattice to break the homogeneous site occupation of an atomic Mott insulator of bosonic 87Rb. We detect the disruption of the ordered Mott domains via noise correlation analysis of the atomic density distribution after time of flight. The appearance of additional correlation peaks evidences the redistribution of the atoms into a strongly inhomogeneous insulating state, in quantitative agreement with the predictions.

V. Guarrera et al.
Noise Correlation Spectroscopy of the Broken Order of a Mott Insulating Phase
Phys. Rev. Lett. 100, 250403 (2008)