Regensburg 2004 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

TT: Tiefe Temperaturen

TT 4: Quantenflüssigkeiten, Bose-Einstein Kondensate, ultrakalte Atome, ...

TT 4.3: Vortrag

Montag, 8. März 2004, 10:45–11:00, H19

Ground state properties and non-equilibrium dynamics of hard-core bosons confined on optical lattices — •Marcos Rigol Madrazo and Alejandro Muramatsu — Institut fuer Theoretische Physik III, Universitaet Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany

We study by means of an exact numerical approach, a gas of hard core bosons (HCB) confined on optical lattices. The ground state properties of such systems are analyzed. Local incompressible phases appear in the system, like in the case of interacting soft-core bosons [1] and fermions [2,3]. The changes in momentum distribution function and in the natural orbitals (effective single particle states) introduced by the formation of such phases are analyzed. We also study non-equilibrium properties for those systems, which within our numerical approach can be obtained exactly for systems with ∼ 200 particles on lattices with ∼ 3000 sites. In particular we analyze the free expansion of the gas when it is released from the trap turning off the confining potential. We show that the expansion is non-trivial (as opposed to the fermionic case) and new features to be observed in the experiments are analyzed.

[1] G. G. Batrouni, V. Rousseau, R. T. Scalettar, M. Rigol, A. Muramatsu,P. J. H. Denteneer, and M. Troyer, Phys. Rev. Lett. 89, 117203 (2002).

[2] M. Rigol, A. Muramatsu, G. G. Batrouni, and R. T. Scalettar, Phys. Rev. Lett. 91, 130403 (2003).

[3] M. Rigol and A. Muramatsu, cond-mat/0309670 (2003).