Coulomb Crystals in a Pulse-Excited Linear Paul Trap

We present results from recent experiments with laser cooled (24)Mg(+) ions captured in a pulse-excited linear Paul trap. As discussed in 1-3, the radial/transverse dynamics of charged particles in an electric quadrupole trap with a pulsed voltage excitation is analogous to that of particles travelling through the alternating gradient (AG) magnetic quadrupole lattice of a storage ring or transport channel. Hence, the pulse-excited Paul quadrupole trap may be used to emulate non-neutral beam propagation. In a series of experiments, we have investigated the stability of stationary Coulomb crystals. The results comply with current theory of crystalline plasmas and beams. We observe, however, that the plasma may stay crystalline beyond the expected stability region in a hitherto unseen configuration consistent with a string of rotating discs.
This article is from CP606, Non-Neutral Plasma Physics IV, p145-150, 2001. Pub. in AIP Conference Proceedings: volume 606. Prepared in cooperation with Ernst-Moritz-Arndt-Universitaet, Greifswald, Germany. This article is from ADA404831 Non-Neutral Plasma Physics 4. Workshop on Non-Neutral Plasmas (2001) Held in San Diego, California on 30 July-2 August 2001