2004/12/09 by U. Fröhlich, B. Roth, S. Schiller · 1 citation
Physics and Astronomy · #physics.plasm-ph #physics.atom-ph
paper · pdf · doi:10.1063/1.1976605
4 pages, 3 figures
arxiv created 2004/12/09 · arxiv updated 2009/12/01
A static quadrupole potential breaks the cylindrical symmetry of the effective potential of a linear rf trap. For a one-component fluid plasma at low temperature, the resulting equilibrium charge distribution is predicted to be an ellipsoid. We have produced laser-cooled Be+ ellipsoidal ion crystals and found good agreement between their shapes and the cold fluid prediction. In two-species mixtures, containing Be+ and sympathetically cooled ions of lower mass, a sufficiently strong static quadrupole potential produces a spatial separation of the species.