M. Bonitz

Quantum kinetic theory

Introduction.- Reduced Density Operators.- Correlations due to the Spin Statistics.- Mean-Field Approximation.- Correlations and their Dynamics.- Non-Markovian Effects.- Kinetic Equations with Selfenergy.- Properties of the Kinetic Equation.- T-Matrix Approximation.- Random Phase Approximation.- Screened Ladder Approximation.- Charged Carriers in EM Fields.- Non-Equilibrium Greens Functions.- Kinetics vs. Molecular Dynamics.- Conclusion.

Complex plasmas: a laboratory for strong correlations

Strong correlations—cooperative behavior due to many-particle interactions—are omnipresent in nature. They occur in electrolytic solutions, dense plasmas, ultracold ions and atomic gases in traps, complex (dusty) plasmas, electrons and excitons in quantum dots and the quark–gluon plasma. Correlation effects include the emergence of long-range order, of liquid-like or crystalline structures and collective dynamic properties (collective modes). The observation and experimental analysis of strong correlations are often difficult, requiring, in many cases, extreme conditions such as very low temperatures or high densities. An exception is complex plasmas where strong coupling can be easily achieved, even at room temperature. These systems feature the strongest correlations reported so far and experiments allow for an unprecedented precision and full single-particle resolution of the stationary and time-dependent many-particle behavior. The governing role of the interactions in strongly correlated systems gives rise to many universal properties observed in all of them. This makes the analysis of one particular system interesting for many others. This motivates the goal of this paper which is to give an overview on recent experimental and theoretical results in complex plasmas including liquid-like behavior, crystal formation, structural and dynamic properties. It is expected that many of these effects will be of interest also to researchers in other fields where strong correlations play a prominent role. (Some figures in this article are in colour only in the electronic version) This article was invited by Gordon Baym.

Wigner Crystallization in Mesoscopic 2D Electron Systems

Wigner crystallization of electrons in 2D quantum dots is reported. It proceeds in two stages: (i) via radial ordering of electrons on shells and (ii) freezing of the intershell rotation. The phase boundary of the crystal is computed in the whole temperature-density plane, and the influences of quantum effects and the particle number are analyzed.

Progress in Nonequilibrium Green's Functions III

This is the third volume (the first two volumes are Progress in Nonequilibrium Greens Functions, M. Bonitz (ed.) and Progress in Nonequilibrium Greens Functions II, M. Bonitz and D. Semkat (eds.), which were published by World Scientific (Singapore), in 2000 and 2003, respectively, (ISBN 981-02-4218-2 and ISBN 981-238-271-2).) of articles on the theory of Nonequilibrium Greens functions (NGF) and their modern applications in various fields. The refereed papers in this volume are based on talks and posters presented at the interdisciplinary conference Progress in Nonequilibrium Greens Functions III which was held in August 2005 at Kiel University, Germany. The conference was attended by about 70 scientists working in a variety of fields of theoretical physics, including plasma physics, solid state theory, semiconductor optics and transport, nanostructures, nuclear matter and high energy physics. Compared to the previous conferences, new topics were covered, such as transport theory for molecular systems, combinations of NGF with (time-dependent) density functional theory or dynamical mean field theory. This reflects modern developments in many-body theory. As with the two previous volumes, this one, hopefully, will be a valuable and stimulating reference for students and researchers from various fields. In contrast to the previous volumes, this one appears as a volume of Journal of Physics: Conference Series. This option was chosen as Journal of Physics: Conference Series offers free access to the online version which also contains color figures. This, hopefully, will increase the distribution of the articles to the scientific community. This conference would not have been possible without the generous financial support from the Deutsche Forschungsgemeinschaft (DFG) and without help from many people. We are particularly grateful to Andrea Fromm, Fanny Geisler and Doris Schulz from the local organizating committee in Kiel and Wolf Dietrich Kraeft (Rostock) for assistence in the final editing of the papers.

Structural Properties of Screened Coulomb Balls

Small three-dimensional strongly coupled charged particles in a spherical confinement potential arrange themselves in a nested shell structure. By means of experiments, computer simulations, and theoretical analysis, the sensitivity of their structural properties to the type of interparticle forces is explored. While the normalized shell radii are found to be independent of shielding, the shell occupation numbers are sensitive to screening and are quantitatively explained by an isotropic Yukawa model.

Theory and simulation of strong correlations in quantum Coulomb systems

Strong correlations in quantum Coulomb systems (QCS) are attracting increasing interest in many fields ranging from dense plasmas and semiconductors to metal clusters and ultracold trapped ions. Examples are bound states in dense plasmas (atoms, molecules, clusters) and semiconductors (excitons, trions, biexcitons) or Coulomb crystals. We present first-principle simulation results of these systems including path integral Monte Carlo simulations of the equilibrium behaviour of dense hydrogen and electron– hole plasmas and molecular dynamics and quantum kinetic theory simulations of the nonequilibrium properties of QCS. Finally, we critically assess potential and limitations of the various methods in their application to Coulomb systems.

Introduction to complex plasmas

Complex Plasmas.- Classical and Quantum Plasmas.- Principles of Transport in Multicomponent Plasmas.- to Quantum Plasmas.- to Quantum Plasma Simulations.- Quantum Effects in Plasma Dielectric Response: Plasmons and Shielding in Normal Systems and Graphene.- Strongly Coupled and Dusty Plasmas.- Imaging Diagnostics in Dusty Plasmas.- Structure and Dynamics of Finite Dust Clusters.- Statistical Theory of Spherically Confined Dust Crystals.- PIC-MCC Simulations of Capacitive High-Frequency Discharge Dynamics with Nanoparticles.- Molecular Dynamics Simulation of Strongly Correlated Dusty Plasmas.- Reactive Plasmas, Plasma-Surface Interaction, Technological Applications.- Nonthermal Reactive Plasmas.- Formation and Deposition of Nanosize Particles on Surfaces.- Kinetic and Diagnostic Studies of Molecular Plasmas Using Laser Absorption Techniques.- X-Ray Diagnostics of Plasma-Deposited Thin Layers.- The Use of Nonthermal Plasmas in Environmental Applications.- Complex (Dusty) Plasmas: Application in Material Processing and Tools for Plasma Diagnostics.

On the wake structure in streaming complex plasmas

The theoretical description of complex (dusty) plasmas requires multiscale concepts that adequately incorporate the correlated interplay of streaming electrons and ions, neutrals and dust grains. Knowing the effective dust-dust interaction, the multiscale problem can be effectively reduced to a one-component plasma model of the dust subsystem. The goal of this paper is a systematic evaluation of the electrostatic potential distribution around a dust grain in the presence of a streaming plasma environment by means of two complementary approaches: (i) a high-precision computation of the dynamically screened Coulomb potential from the dynamic dielectric function and (ii) full 3D particle-in-cell simulations, which self-consistently include dynamical grain charging and nonlinear effects. The range of applicability of these two approaches is addressed.

Thermodynamics of hot dense H-plasmas: path integral Monte Carlo simulations and analytical approximations

This work is devoted to the thermodynamics of high-temperature dense hydrogen plasmas in the pressure region between 10-1 and 102 Mbar. In particular, we present for this region results of extensive calculations based on a recently developed path integral Monte Carlo scheme (direct PIMC). This method allows for a correct treatment of the thermodynamic properties of hot dense Coulomb systems. Calculations were performed in a broad region of the non-ideality parameter Γ3 and degeneracy parameter neΛ310. We give a comparison with a few available results from other path integral calculations (restricted PIMC) and with analytical calculations based on Pade approximations for strongly ionized plasmas. Good agreement between the results obtained from the three independent methods is found.

Classical and quantum Coulomb crystals

Strong correlation effects in classical and quantum plasmas are discussed. In particular, Coulomb (Wigner) crystallization phenomena are reviewed focusing on one-component non-neutral plasmas in traps and on macroscopic two-component neutral plasmas. The conditions for crystal formation in terms of critical values of the coupling parameters and the distance fluctuations and the phase diagram of Coulomb crystals are discussed.