title: Monopole excitations of a harmonically trapped one-dimensional Bose gas from the ideal gas to the Tonks-Girardeau regime.
abstract: Using a time-dependent modified nonlinear Schrödinger equation (MNLSE)-where the conventional chemical potential proportional to the density is replaced by the one inferred from Lieb-Liniger's exact solution-we study frequencies of the collective monopole excitations of a one-dimensional Bose gas. We find that our method accurately reproduces the results of a recent experimental study [E. Haller et al., Science 325, 1224 (2009)] in the full spectrum of interaction regimes from the ideal gas, through the mean-field regime, through the mean-field Thomas-Fermi regime, all the way to the Tonks-Giradeau gas. While the former two are accessible by the standard time-dependent NLSE and inaccessible by the time-dependent local density approximation, the situation reverses in the latter case. However, the MNLSE is shown to treat all these regimes within a single numerical method.
authors.affiliation: Department of Physics, University of Massachusetts, Boston, Massachusetts 02125, USA.
authors.forename: S
authors.initials: S
authors.lastname: Choi
authors.affiliation: Department of Physics, University of Massachusetts, Boston, Massachusetts 02125, USA.
authors.forename: V
authors.initials: V
authors.lastname: Dunjko
authors.affiliation: Department of Physics, University of Massachusetts, Boston, Massachusetts 02125, USA.|Department of Physics and Astronomy, SUNY, Stony Brook, New York 11794, USA.
authors.forename: Z D
authors.initials: ZD
authors.lastname: Zhang
authors.affiliation: Department of Physics, University of Massachusetts, Boston, Massachusetts 02125, USA.
authors.forename: M
authors.initials: M
authors.lastname: Olshanii