title: Transverse breathing mode of an elongated Bose-Einstein condensate.
abstract: We study experimentally the transverse monopole mode of an elongated rubidium condensate. Because of the scaling invariance of the nonlinear Schrödinger (Gross-Pitaevskii) equation, the oscillation is monochromatic and sinusoidal at short times, even under strong excitation. For ultralow temperatures, the quality factor Q = omega(0)/gamma(0) can exceed 2000, where omega(0) and gamma(0) are the mode angular frequency and damping rate. This value is much larger than any previously reported for other eigenmodes of a condensate. We also present the temperature variation of omega(0) and gamma(0).
authors.affiliation: Laboratoire Kastler Brossel, 24 rue Lhomond, 75005 Paris, France.
authors.forename: F
authors.initials: F
authors.lastname: Chevy
authors.forename: V
authors.initials: V
authors.lastname: Bretin
authors.forename: P
authors.initials: P
authors.lastname: Rosenbusch
authors.forename: K W
authors.initials: KW
authors.lastname: Madison
authors.forename: J
authors.initials: J
authors.lastname: Dalibard