Simulations of an ultracold, neutral plasma with equal masses

TL;DR

This paper presents a theoretical study of an ultracold, neutral plasma with equal positive and negative charges, focusing on its early evolution, temperature dynamics, and recombination processes through simulations.

Contribution

It introduces simulations of an ultracold plasma with equal masses, exploring its formation, temperature evolution, and expansion behavior in different coupling regimes.

Findings

Initial energy controls plasma temperature and coupling regime.

Recombination and thermalization processes depend on density and temperature.

Expansion dynamics influence velocity distribution over time.

Abstract

The results of a theoretical investigation of an ultracold, neutral plasma composed of equal mass positive and negative charges are reported. In our simulations, the plasma is created by the fast dissociation of a neutral particle. The temperature of the plasma is controlled by the relative energy of the dissociation. We studied the early time evolution of this system where the initial energy was tuned so that the plasma is formed in the strongly coupled regime. In particular, we present results on the temperature evolution and three body recombination. In the weakly coupled regime, we studied how an expanding plasma thermalizes and how the scattering between ions affects the expansion. Because the expansion causes the density to drop, the velocity distribution only evolves for a finite time with the final distribution depending on the number of particles and initial temperature of the plasma.