Thermodynamic State Variables in Quasi-Equilibrium Ultracold Neutral Plasma

Abstract

The pressure and internal energy of an ultracold plasma in a state of quasi-equilibrium are evaluated using classical molecular dynamics simulations. Coulomb collapse is avoided by modeling electron-ion interactions using an attractive Coulomb potential with a repulsive core. We present a method to separate the contribution of classical bound states, which form due to recombination, from the contribution of free charges when evaluating these thermodynamic state variables. It is found that the contribution from free charges is independent of the choice of repulsive core length-scale when it is sufficiently short-ranged. The partial pressure associated with the free charges is found to closely follow that of the one-component plasma model, reaching negative values at strong coupling, while the total system pressure remains positive. This pseudo-potential model is also applied to Debye-Hückel theory to describe the weakly coupled regime.

References in corpus (5)

• Ultracold Neutral Plasmas
• Molecular Dynamics Simulations of Temperature Equilibration in Dense Hydrogen
• Using Three-Body Recombination to Extract Electron Temperatures of Ultracold Plasmas
• Extending plasma transport theory to strong coupling through the concept of an effective interaction potential
• Experimental measurement of non-Markovian dynamics and self-diffusion in a strongly coupled plasma

Cited by in corpus (8)

• Pair Correlation Functions of Strongly Coupled Two-Temperature Plasma
• Strong Coulomb Coupling Influences Ion and Neutral Temperatures in Atmospheric Pressure Plasmas
• Reduction of electron heating by magnetizing ultracold neutral plasma
• Structure formation by electrostatic interactions in strongly coupled medium
• Electron Temperature Relaxation in the Clusterized Ultracold Plasmas
• Mean Force Emission Theory for Classical Bremsstrahlung in Electron-Ion Plasmas
• Hollow Beam Optical Ponderomotive Trap for Ultracold Neutral Plasma
• The Barkas Effect in Plasma Transport