title: Melting scenarios for three-dimensional dusty plasma clusters.
abstract: The melting transition of finite three-dimensional dust clouds (Yukawa balls) from a solid-like to a liquid-like state is systematically studied with high spatial and temporal resolution of the individual grains by means of stereoscopy. Two different melting scenarios are reported: Melting is induced first by an increase of plasma power, and second by laser-induced heating. The experiments confirm that melting starts with a loss of orientational correlation, followed by a loss of the radial order upon further heating. While the plasma-power melting is driven via the ion wakefield, laser heating provides a more equilibrium scenario. The internal loss of correlations is well captured by the triple correlation function (TCF) which is insensitive to particle exchanges and the rotation of the cluster as a whole. The critical Coulomb coupling parameter for N=35 is determined as Γ(crit)≈570. The experimental findings are in good agreement with thermodynamic Monte Carlo simulations.
authors.affiliation: Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, Greifswald, Germany.
authors.forename: André
authors.initials: A
authors.lastname: Schella
authors.forename: Tobias
authors.initials: T
authors.lastname: Miksch
authors.forename: André
authors.initials: A
authors.lastname: Melzer
authors.forename: Jan
authors.initials: J
authors.lastname: Schablinski
authors.forename: Dietmar
authors.initials: D
authors.lastname: Block
authors.forename: Alexander
authors.initials: A
authors.lastname: Piel
authors.forename: Hauke
authors.initials: H
authors.lastname: Thomsen
authors.forename: Patrick
authors.initials: P
authors.lastname: Ludwig
authors.forename: Michael
authors.initials: M
authors.lastname: Bonitz
mesh_terms: D000465:Algorithms; D003102:Colloids / Q000737:chemistry*; D004391:Dust; D004867:Equipment Design; D005615:Freezing; D005898:Glass; D007834:Lasers; D015233:Models, Statistical; D009010:Monte Carlo Method; D010825:Physics / Q000379:methods*; D013696:Temperature; D013816:Thermodynamics
chemical_list: D003102:Colloids; D004391:Dust