Evolution of condensate fraction during rapid lattice ramps

Stefan S. Natu, David C. McKay, Brian DeMarco, Erich J. Mueller
2012 Physical Review A. Atomic, Molecular, and Optical Physics  
Combining experiments and numerical simulations, we investigate the redistribution of quasi-momentum in a gas of atoms trapped in an optical lattice when the lattice depth is rapidly reduced. We find that interactions lead to significant momentum redistribution on millisecond timescales, thereby invalidating previous assumptions regarding adiabaticity. We show that this phenomenon is driven by the presence of low-momentum particle-hole excitations in an interacting system. Our results
more » ... bandmapping as an equilibrium probe in interacting gases.
doi:10.1103/physreva.85.061601 fatcat:vsdtxxrpo5edph5jwsd2dg44ja