G. Kalman

STRONGLY COUPLED COULOMB SYSTEMS

Review Papers: Equation of State for Binary Ionic Plasmas, Fluid and Solid Plasma H.D. Dewitt, W.L. Slattery. Ionic Liquids: Investigations of Condensed Matter by Inelastic X-Ray Scattering with High Energy Resolution E. Burkel, et al. Multicomponent and Astrophysical Plasmas: Thermodynamic and Structural Properties of Strongly Coupled Plasma Mixtures from the Perturbative HNC Equation H.S. Kang, F.H. Ree. Dusty Plasmas: Unified Kinetic Theory for Fluid and Crystal Phases J.W. Dufty, S.P. Das. White Dwarfs: Crystallizing White Dwarfs J. Isern, et al. Density Functional Theory: DFT Calculations for Compressed Aluminium: (i) K-Edge Spectra of Al from Solid to Liquid to Plasma (ii) Energy-Relaxation in a Two-Temperature Al-Plasma M.W.C. Dharma-Wardana. Equation of State: Equation of State of Shock Compressed Plasma of Metals V.E. Fortov, et al. Hydrogen: Spectroscopy: Electrolytes, Colloidal Suspension: Charged Particle Traps, Non-Neutral Plasmas: Electron Liquid: Quantum Dots, Hubbard Model, Semiconductor Plasmas: Bilayers: Fusion Plasmas: Dense Plasmas: Weakly Coupled Plasmas: Ionization and Bound States: Response Functions: Statistical Physics: 124 additional articles. Author Index. Subject Index.

Quasilocalized charge approximation in strongly coupled plasma physics

The quasilocalized charge approximation (QLCA) was proposed in 1990 [G. Kalman and K. I. Golden, Phys. Rev. A 41, 5516 (1990)] as a formalism for the analysis of the dielectric response tensor and collective mode dispersion in strongly coupled Coulomb liquids. The approach is based on a microscopic model in which the charges are quasilocalized on a short-time scale in local potential fluctuations. The authors review the application of the QLC approach to a variety of systems which can exhibit strongly coupled plasma behavior: (i) the one-component plasma (OCP) model in three dimensions (e.g., laser-cooled trapped ions) and (ii) in two dimensions (e.g., classical 2D electron liquid trapped above the free surface of liquid helium), (iii) binary ionic mixture in a neutralizing uniform background (e.g., carbon–oxygen white dwarf interiors), (iv) charged particle bilayers (e.g., semiconductor electronic bilayers), and (v) charged particles in polarizable background (e.g., laboratory dusty plasmas).

NONLINEAR FLUCTUATION--DISSIPATION THEOREM.

Using statistical mechanical perturbation theory, the second-order average current density response is calculated for magnetic field-free classical plasmas. A dynamical fluctuation-dissipation theorem is then derived, thus establishing a connection between triplet microscopic current-current correlations and quadratic response functions; it also leads to a static fluctuation-dissipation theorem which provides a dielectric description of the equilibrium ternary correlation. A comparison of the latter with its expansion in terms of the Mayer pair correlation clusters is discussed.

Dynamics of two-dimensional dipole systems

Using a combined analytical/molecular dynamics approach, we study the current fluctuation spectra and longitudinal and transverse collective mode dispersions of the classical two-dimensional (point) dipole system (2DDS) characterized by the ϕ{D}(r)=μ{2}/r{3} repulsive interaction potential; μ is the electric dipole strength. The interest in the 2DDS is twofold. First, the quasi-long-range 1/r{3} interaction makes the system a unique classical many-body system, with a remarkable collective mode behavior. Second, the system may be a good model for a closely spaced semiconductor electron-hole bilayer, a system that is in the forefront of current experimental interest. The longitudinal collective excitations, which are of primary interest for the liquid phase, are acoustic at long wavelengths. At higher wave numbers and for sufficiently high coupling strength, we observe the formation of a deep minimum in the dispersion curve preceded by a sharp maximum; this is identical to what has been observed in the dispersion of the zero-temperature bosonic dipole system, which in turn emulates so-called roton-maxon excitation spectrum of the superfluid 4He . The analysis we present gives an insight into the emergence of this apparently universal structure, governed by strong correlations. We study both the liquid and the crystalline solid state. We also observe the excitation of combination frequencies, resembling the roton-roton, roton-maxon, etc. structures in 4He .

Phases in strongly coupled electronic bilayer liquids

The strongly correlated liquid state of a bilayer of charged particles has been studied via the hypernetted chain calculation of the two-body functions. We report the first time emergence of a series of structural phases, identified through the behavior of the two-body functions.

Plasmon dispersion for strong coupling

Abstract The integral equation for the frequency dependent dielectric response function as given by the Golden-Kalman strongly coupled plasma approximation scheme is solved for a one component plasma in the k → 0 limit through a simple hydrodynamical “ansatz” for the response function. The self-consistency requirement appears through algebraic relations for the plasmon dispersion and damping coefficients A(γ) and B(γ).

Superdense neutron matter

We present a relativistic therory of high-density matter which takes into account the short-range interaction due to the exchange of spin-2 mesons. An equation of state is derived and used to compute neutron star properties. The prediction of our theory for the values of maximum mass and moment of inertia for a stable neutron star are 1.75 M/sub sun/ and 1.68 x 10/sup 4/5 g cm/sup 2/, in very good agreement with the presently known observational bounds. The corresponding radius is found to be 10.7 km.We find that the inclusion of the spin-2 interaction reduces the disagreement between the relativistic and nonrelativistic theories in their predictions of masses and moments of inertia.

Collective Dynamics of Complex Plasma Bilayers

A classical dusty plasma experiment was performed using two different dust grain sizes to form a strongly coupled asymmetric bilayer (two closely spaced interacting monolayers) of two species of charged dust particles. The observation and analysis of the thermally excited particle oscillations revealed the collective mode structure and dispersion (wave propagation) in this system; in particular, the existence of the theoretically predicted k=0 energy (frequency) gap was verified. Equilibrium molecular-dynamics simulations were performed to emulate the experiment, assuming Yukawa-type interparticle interaction. The simulations and analytic calculations based both on lattice summation and on the quasilocalized charge approximation approach are in good agreement with the experimental findings and help in identifying and characterizing the observed phenomena.

Molecular Dynamics Studies of Solid–Liquid Phase Transition in 2-D Yukawa Systems

We present systematic studies aimed at investigating the precise details of solid-liquid phase transition in 2-D classical many-particle systems interacting with the Yukawa potential. This is done by introducing and analyzing a variety of indicators, such as the bond angular order parameter, the angular distribution of the Einstein oscillations, local angular correlations, global positional correlations, and the variation of internal energy in the vicinity of the melting temperature. Our results consequently show rapid changes around Gamma=415 for kappamacr=2 of the investigated quantities

Two-dimensional Yukawa liquids: structure and collective excitations

The paper reports molecular dynamics (MD) simulations on two-dimensional, strongly-coulped Yukawa liquids. An effective coupling coefficient Γ* for the liquid phase is identified; thermodynamic properties such as internal energy, pressure and compressibility, as well as longitudinal and transverse mode dispersions are analysed.