Suppression of the critical temperature for superfluidity near the Mott transition: validating a quantum simulator

Note: 10:00 AM
Speaker: Lode Pollet, Harvard University

When: February 17, 2010 (Wed), 10:00AM to 11:00AM (add to my calendar)

This event is part of the Condensed Matter Theory Seminar Series.

Abstract: Ultra-cold atoms in an optical lattice offer an unique opportunity to study prototypical models of condensed matter physics, serving as quantum simulators. Before they can be trusted for unknown models, they first need to be validated against known models. This benchmarking is the topic of the present study, where we compare the phase diagram of the Bose-Hubbard model obtained in experiment (group of I. Bloch) and numerics. We present the first full ab-initio comparison for strongly interacting Bose gases on a lattice for large systems (up to 300,000 atoms). The comparison has enabled us to perform thermometry for the interacting quantum gas to experimentally determine the finite temperature phase diagram for bosonic superfluids in an optical lattice, and check the validity of the conservation of entropy assumption. Our results reveal a downshift of the critical temperature as the transition to the Mott insulator is approached.

Ref: S. Trotzky et al., arXiv:0905.4882