Evidence for highly charged ion Coulomb crystallization in multicomponent strongly coupled plasmas

Multicomponent non-neutral ion plasmas in a Penning trap consisting of Be+ and highly charged Xe ions, having different mass-to-charge ratios than Be+, are cooled to form strongly coupled plasmas by applying a laser-based collisional cooling scheme. The temperature of the plasma was determined from a Doppler broadened transition in Be+. For the Xe ions, which are centrifugally separated from the Be, the Coulomb coupling parameter was estimated to be approximate to 1000. Molecular dynamics simulations of the ion mixture show ordered structures, indicating crystallization of the Xe.