Dipole oscillations of confined lattice bosons in one dimension

We study the dynamics of a nonintegrable system comprising interacting cold bosons trapped in an optical lattice in one dimension by means of exact time-dependent numerical density-matrix renormalization group techniques. Particles are confined by a parabolic potential, and dipole oscillations are induced by displacing the trap center of a few lattice sites. Depending on the system parameters this motion can vary from undamped to overdamped. We study the dipole oscillations as a function of the lattice displacement, the particle density, and the strength of interparticle interactions. These results explain the recent experiment [ C. D. Fertig et al. Phys. Rev. Lett. 94 120403 (2005)].