title: Coulomb expansion of laser-excited ion plasmas.
abstract: We determine the electric field in mm-sized clouds of cold Rb+ ions, produced by photoionization of laser-cooled 87Rb atoms in a magneto-optical trap, using the Stark effect of embedded Rydberg atoms. The dependence of the electric field on the time delay between the ion plasma production and the probe of the electric field reflects the Coulomb expansion of the plasma. Our experiments and models show expansion times <1micros.
authors.affiliation: FOCUS Center, Physics Department, University of Michigan, 500 East University, Ann Arbor, Michigan 48109-1120, USA.
authors.forename: D
authors.initials: D
authors.lastname: Feldbaum
authors.forename: N V
authors.initials: NV
authors.lastname: Morrow
authors.forename: S K
authors.initials: SK
authors.lastname: Dutta
authors.forename: G
authors.initials: G
authors.lastname: Raithel