Creating Non-Maxwellian Velocity Distributions in Ultracold Plasmas

TL;DR

This paper introduces methods to manipulate and analyze ion velocity distributions in ultracold plasmas, enabling the creation of non-Maxwellian distributions and detailed measurement techniques.

Contribution

It develops optical pumping and fluorescence spectroscopy techniques to perturb and measure ion velocities, validated by molecular dynamics simulations.

Findings

Successful creation of non-Maxwellian velocity distributions

Effective extraction of velocity profiles from fluorescence spectra

Agreement between experimental results and simulations

Abstract

We present techniques to perturb, measure and model the ion velocity distribution in an ultracold neutral plasma produced by photoionization of strontium atoms. By optical pumping with circularly polarized light we promote ions with certain velocities to a different spin ground state, and probe the resulting perturbed velocity distribution through laser-induced fluorescence spectroscopy. We discuss various approaches to extract the velocity distribution from our measured spectra, and assess their quality through comparisons with molecular dynamic simulations