2005/03/01 by T. Pohl, Thomas Pohl, T. Pattard +3 · 57 citations
Physics and Astronomy · #Atomic physics #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Coulomb #Coupling (piping) #Dust and Plasma Wave Phenomena #Ion #Ionic bonding #Materials science #Non-equilibrium thermodynamics #Physics #Plasma #Quantum mechanics #Relaxation (psychology) #Theoretical and Computational Physics #Thermodynamics #physics.atom-ph #physics.plasm-ph
paper · pdf · doi:10.1103/physrevlett.94.205003
published in Physical Review Letters 94(20), 205003 (American Physical Society)
arxiv created 2005/03/01 · openalex publication_date 2005/05/24 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the strongly correlated ion dynamics and the degree of coupling achievable in the evolution of freely expanding ultracold neutral plasmas. We demonstrate that the ionic Coulomb coupling parameter Gamma(i) increases considerably in later stages of the expansion, reaching the strongly coupled regime despite the well known initial drop of Gamma(i) to order unity due to disorder-induced heating. Furthermore, we formulate a suitable measure of correlation and show that Gamma(i) calculated from the ionic temperature and density reflects the degree of order in the system if it is sufficiently close to a quasisteady state. At later times, however, the expansion of the plasma cloud becomes faster than the relaxation of correlations, and the system does not reach thermodynamic equilibrium anymore.