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Observation of Three-dimensional Long-range Order in Smaller Ion Coulomb Crystals in an rf Trap

A. Mortensen·E. Nielsen·T. Matthey·M. Drewsen
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Abstract

Three-dimensional long-range ordered structures in smaller and near-spherically symmetric Coulomb crystals of ^{40}Ca^+ ions confined in a linear rf Paul trap have been observed when the number of ions exceeds ~1000 ions. This result is unexpected from ground state molecular dynamics (MD) simulations, but found to be in agreement with MD simulations of metastable ion configurations. Previously, three-dimensional long-range ordered structures have only been reported in Penning traps in systems of ~50,000 ions or more.

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A. Mortensen, E. Nielsen, T. Matthey, M. Drewsen. 2006-02-14. Observation of Three-dimensional Long-range Order in Smaller Ion Coulomb Crystals in an rf Trap. https://doi.org/10.1103/physrevlett.96.103001

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