Hannover 2010 – wissenschaftliches Programm
P 22.3: Poster
Donnerstag, 11. März 2010, 16:00–18:00, Lichthof
Thermodynamic Theory of Spherically Trapped Coulomb Clusters — Jeffrey Wrighton1, James Dufty1, •Henning Bruhn2, Hanno Kählert2, and Michael Bonitz2 — 1Department of Physics, University of Florida, Gainesville, FL 32611 — 2ITAP, Christian-Albrechts Universität zu Kiel, 24098 Kiel
The radial density profile of a finite number of identical charged particles confined in a harmonic trap is computed over a wide ranges of temperatures (Coulomb coupling) and particle numbers. At low temperatures these systems form a Coulomb crystal with spherical shell structure which has been observed in ultracold trapped ions and in dusty plasmas. The shell structure is readily reproduced in simulations. However, analytical theories which used a mean field approach  or a local density approximation  have, so far, only been able to reproduce the average density profile. Here we present an approach to Coulomb correlations based on the hypernetted chain approximation with additional bridge diagrams. It is demonstrated that this model reproduces the correct shell structure within a few percent and provides the basis for a thermodynamic theory of Coulomb clusters in the strongly coupled fluid state [3,4].
 C. Henning et al., Phys. Rev. E 74, 056403 (2006)
 C. Henning et al., Phys. Rev. E 76, 036404 (2007)
 J. Wrighton, J. W. Dufty, H. Kählert, and M. Bonitz, accepted
for publication in Phys. Rev. E, arXiv:0909.0775
 J. Wrighton, J. W. Dufty, M. Bonitz, and H. Kählert, Contrib.
Plasma Phys. (2009)