Experimental measurement of non-Markovian dynamics and self-diffusion in a strongly coupled plasma

Abstract

We present a study of the collisional relaxation of ion velocities in a strongly coupled, ultracold neutral plasma on short timescales compared to the inverse collision rate. Non-exponential decay towards equilibrium for the average velocity of a tagged population of ions heralds non-Markovian dynamics and a breakdown of assumptions underlying standard kinetic theory. We prove the equivalence of the average-velocity curve to the velocity autocorrelation function, a fundamental statistical quantity that provides access to equilibrium transport coefficients and aspects of individual particle trajectories in a regime where experimental measurements have been lacking. From our data, we calculate the ion self-diffusion constant. This demonstrates the utility of ultracold neutral plasmas for isolating the effects of strong coupling on collisional processes, which is of interest for dense laboratory and astrophysical plasmas.

5 figures, 8 pages

References in corpus (6)

• Experimental Realization of an Exact Solution to the Vlasov Equations for an Expanding Plasma
• Self-Diffusion in 2D Dusty Plasma Liquids: Numerical Simulation Results
• Velocity Relaxation in a Strongly Coupled Plasma
• Superdiffusion in quasi-two-dimensional Yukawa liquids
• Ion Temperature Evolution in an Ultracold Neutral Plasma
• Demonstrating Universal Scaling in Quench Dynamics of a Yukawa One-Component Plasma

Cited by in corpus (17)

• Mean Force Kinetic Theory: a Convergent Kinetic Theory for Weakly and Strongly Coupled Plasmas
• Testing thermal conductivity models with equilibrium molecular dynamics simulations of the one component plasma
• Effective Potential Theory for Diffusion in Binary Ionic Mixtures
• Simple dispersion relations for Coulomb and Yukawa fluids
• Thermodynamic State Variables in Quasi-Equilibrium Ultracold Neutral Plasma
• Self-diffusion in single-component Yukawa fluids
• Dissipative dynamics of atomic and molecular Rydberg gases: Avalanche to ultracold plasma states of strong coupling
• Ion friction at small values of the Coulomb logarithm
• Reduction of electron heating by magnetizing ultracold neutral plasma
• Fractional Laplacian Spectral Approach to Turbulence in a Dusty Plasma Monolayer
• Reduced Ionic Diffusion by the Dynamic Electron-Ion Collisions in Warm Dense Hydrogen
• Expansion of Ultracold Neutral Plasmas with Exponentially Decaying Density Distributions
• FPGA based demodulation of laser induced fluorescence in plasmas
• Velocity space degrees of freedom of plasma fluctuations
• A technique for plasma velocity-space cross-correlation
• Intrinsic bulk viscosity of the one-component plasma
• Many-body collision contributions to electron momentum damping rates in a plasma influenced by electron strong coupling