Cubic barium titanate (BaTiO3) thin films have been prepared in situ, on a low-temperature substrate, Al/SiO2/Si(100), by intense, pulsed ion beam evaporation. We have first proposed a new deposition configuration, backside deposition, which, in comparison with standard frontside deposition, produces very smooth thin films, Rα (mean roughness) ≈ 3 ∼ 9 nm, without any droplets. There is no significant change of the dielectric constant in the frequency range of 10 ∼ 105 Hz. The dielectric constant for the film deposited at the substrate temperature of 200˚C is typically ∼90 at 1 kHz.

Achieving inertial confinement fusion using a light-ion-beam driver requires continued improvement in understanding ion diode physics. The power delivered to a light-ion beam target is strongly influenced by the evolution of the charge-particle distributions across the ion beam acceleration gap. Our strategy is to determine this evolution from time- and space-resolved measurements of the electric field using Stark-shifted line emission. In addition to diode physics, the unique high-field (∼10 MV/cm, ∼6T) conditions in present experiments offer the possibility to advance basic atomic physics, for example by measuring field ionization rates for tightly bound low-principal-quantum-number levels. In fact, extension of atomic physics into the high-field regime is required for accurate interpretation of diode physics measurements. This paper describes progress in ion diode physics and basic atomic physics, obtained with visible-light atomic spectroscopy measurements in the ∼20 TW Particle Beam Fusion Accelerator II ion diode.

We present the results of calculations for the K-edges of representative transient carbon ion clusters in a dense carbon plasma. The calculations use the recently implemented non-“muffin-tin” scattered-wave method previously used in the molecular and solid-state fields. Based on a simple model for the cluster potentials it is shown that, compared with a single ion calculation, the presence of neighboring ions can significantly alter the K-edge photoionization cross sections, and hence the resulting opacities.

The main objective of the experimental plasma physics activities at the Gesellschaft für Schwerionenforschung (GSI) is the interaction processes of heavy ions with dense ionized matter. Gas discharge plasma targets were used for energy loss and charge state measurements in a regime of electron density and temperature up to 1019 cm-3 and 20 eV, respectively. Progress has been achieved in the understanding of charge-exchange processes in fully ionized hydrogen plasma. An improved model taking excitation-autoionization processes into account has removed most of the discrepancies of previous theoretical descriptions. Furthermore, it was found that the energy loss of the ion beam serves as an excellent diagnostic tool for measuring the electron density in partially ionized plasmas such as argon. The experience with these methods will be used in the future to diagnose dense laser produced plasmas. A setup with a 100 J/5 GW Nd:glass laser, currently under construction, will provide access to density range up to 1021 cm-3 and temperatures of more than 100 eV. To reach electron densities near solid-state density (1023 cm-3), heavy ion heated frozen rare gas crystals were used. The first hydrodynamic motion of ion heated solid material was observed. Vacuum-ultraviolet (VUV) spectroscopy was applied to diagnose these strongly coupled nonideal plasmas.

Parametric electron-ion potential for fast estimation of atomic data required for “on-line” calculations in inertial confinement fusion (ICF) driven by heavy ions is presented. Comparisons of our results (outer- and inner-shell ionization energies, oscillator strengths, and logarithmic mean excitation energies) with experimental and self-consistent-field (SCF) calculation values are made. Using the wave functions generated by the previously mentioned potential, generalized oscillator strengths and integrated inelastic collision cross sections are computed within the frame of Born approximation.

In this paper we determine the inelastic contribution to the energy losses by swift heavy ions in dense matter. At equilibrium, the charge transfer stopping is determined by a simple energy balance and the excitation stopping is determined by the photons emission. Using an average atom model, we determine the density influence on these inelastic stoppings.

Experiments are presented that demonstrate the high stopping power of fully ionized hydrogen plasma for low-energy heavy ions. A plasma with electron densities up to 7.1016 cm–3 at temperatures above 1 eV was created by an electrical discharge. In the described experiment, a stopping power of 1.08 GeV/(mg/cm2) was measured using singly charged krypton ions at 45–keV/u energy. The measured stopping power exceeds the corresponding value in cold hydrogen gas by a factor of 35. These measurements confirm the theoretical stopping power predictions close to the expected maximum in a fully ionized plasma.

Classical molecular dynamics of the ions and quantum treatment of the electrons are combined in the study of the properties of hot, dense plasmas. An effective ionic interaction potential is used in the molecular dynamics simulations. The electronic density of states is calculated using the equation of motion method. Special attention is given to the broadening of resonances in the electronic density of states, which may have important effects on the thermodynamic properties of the plasma.

The stopping power of dense nonideal plasmas is calculated in different many-body approximations. The T-matrix approximation of binary collisions is compared with the random phase approximation (RPA) approximation of dielectric fluctuations. It is found that RPA contributions are more important for dense plasmas at low temperatures. Within a microscopic model, the dynamical evolution of the velocity of the projectile is calculated. It reproduces experimental values well for the stopping of fast heavy ions at times after a pinch discharge. Further improvements due to memory effects and relaxation fields are discussed. A renormalization of the effective energy transfer by memory effects is presented.

A study is presented to find a compact X-ray laser in the spectral range of the water window. A double laser pulse method that requires a minimum energy with an optimal timing is proposed. The precreated plasma with an optimal ion distribution is heated by a short second pulse creating the required population inversion. In particular, the Ni-like 4d→4p transitions in tantalum, tungsten, and cesium are calculated.

A numerical model for opacity calculations by using a family of analytical potentials for each configuration in the plasma is presented. The obtained numerical opacity results with this model are compared with those obtained by using a self-consistent potential model.

Intense ion beams can be used to generate ultrahigh pressures in condensed matter. Lightion beams generated at the Karlsruhe Light Ion Facility (KALIF) typically have a focus of less than 1-cm diameter. The maximum power density at KALIF achieved so far is of the order of 1 TW/cm2. In the energy deposition zone of the targets, the 1.5-MeV protons of the KALIF beam deposit energy of the order of 100 TW/g or 5 MJ/g. A strongly coupled, hot, dense plasma is thus created by the action of a light ion beam on matter. The high pressure generated in this region has been used to accelerate thin foils to velocities up to 12.5 km/s. A successful interpretation of these experiments can serve as a check of theoretical models and of the equation of state (EOS) data. The present paper contains an investigation of the hydrodynamics of thin aluminum foil accelerated by light ion beams at KALIF using Bθ0-diode. The peak power density in these experiments was 0.15 ± 0.05 TW/cm2. The results of simulations depend mainly on two factors: power density evolution at the target and the EOS for the strongly coupled dense and hot plasma. The beam power density evolution has been carefully remeasured recently. It turned out that the available EOS data do not reproduce experimental results satisfactorily. We have formulated a simple EOS formula in a modified Mie-Grüneisen form. We assume the Grüneisen parameter to be a function of temperature and density. The parameters of this EOS have been adjusted to reproduce experiments at KALIF. In the present paper analysis of beam-target interaction experiments at KALIF is presented using our analytic EOS. We show that such experiments can give information on EOS data in the region of strongly coupled plasma.

In this paper we compare the requirements for a light ion beam driven inertial confinement fusion (ICF) reactor with the present achievements in pulsed power technology, ion diode performance, beam transport, and target physics. The largest gap exists in beam quality and repetition rate capability of high-power ion diodes. Beam quality can very likely be improved to a level sufficient for driving a single-shot ignition facility, if the potential of two-stage acceleration is used. Present schemes for repetition rate ion diodes allow either too low power densities or create too large beam divergence. On the other hand, repetitively operating pulsed-power generators meeting the requirements for an ICF reactor driver can be built with present technology. Also, a rather mature target concept has been developed for indirect drive with light ion beams.

Conical microducts and minithrottles can be used to accelerate micropellets of fusionable fuel up to very high speeds (∼108 cm/s). The central collision of two pellets flying in opposite directions can produce a hot plasma where fusion reactions are triggered. The main drawback of this scheme is the short confinement time provided by the external guide tube (throttle). To obtain high yield, an extra force of confinement is advisable. In this paper, the performance of fuel implosions within conical targets and the effect of ultrashort magnetic fields and pinch forces are analyzed. Although very high currents are needed to stretch the confinement time, modern technologies based on pulse-power machines and fast discharges induced by ultrashort lasers can provide a solution to this problem.

Evidence of gain in a recombining Z-pinch plasma has been obtained at 52 and 49.8 nm. The amplified XUV radiation originated from the 4f-3d and the 4d-3p transitions of Lilike oxygen, OVI. The plasmas were generated in a small diameter Z-pinch discharge with moderate currents of 40 kA. The gain coefficient was determined by variation of the pinch tube length, leading to a gain-length product of 2.5 (4f-3d) and of 2.2 (4d-3p) for a length of 9 cm.

Evidence will first be presented in favor of the usefulness of coordination number-dependent equations of state of metallic plasmas. After some theoretical discussion of the way such an equation of state may be related to dimer properties, with specific regard to Na and Al, critical point predictions for the alkalis will be brought into contact with experiments. In this context, some results on W will also be surveyed. Structural properties, static and dynamic, will then be considered in relation to transport in both Cu and H plasmas. This will embrace experiments on electrical resistivity in both examples. For H, a simple inference can be extracted about the structure factor, and the discussion will finally be generalized to treat the metalization of solid H.

The stopping at low (V < Vth) and high (V ≤ Vth) velocity, of N strongly correlated ion debris is investigated for the case of a dense and classical electron target. The considered topologies of cluster projectile charges are taken cubic like, and circular, respectively. A specific emphasis is given to the N-dependence, and also to the topological features of the corresponding enhanced correlated stopping.

A brief discussion of the standard theory of line broadening is presented together with an analysis of selected laser-driven implosion experiments. The effect of improved theoretical procedures on experimental analysis is discussed. In particular, we consider the combined effects of ion dynamics and opacity on line profiles used in the analysis of these plasmas. The experiments discussed were performed at the University of Rochester Laboratory for Laser Energetics (LLE). The results presented in this paper illustrate the usefulness of plasma line broadening in diagnosing hot dense plasmas and in understanding fundamental plasma processes.