Time and space-resolved emission spectroscopy measurements were performed to investigate plasma dynamics during laser evaporation of a graphite target in an ambient inert atmosphere. Intense molecular emission is found to occur behind a front separating the plasma from the foreign gas. Two stages of expansion are found and are well described, using a viscous drag force model for the first one and a delayed ideal blast wave model for the second. The vibrational temperature estimated using the Swan band in helium at different pressures is presented.

The acceleration of transparent charged macroparticles by the repeated radiation pressure of a laser beam is considered. A radial electric field allows a motion along a closed path, on a stable orbit. For macroparticles made out of carborundum, of radius r = 0.5 μm, velocities above 100 km/s look feasible, allowing the production of high densities of energy.

Basic relations are presented to calculate isotope enrichment and depletion factors in a supercooled flow of gaseous QF6 molecules mixed with Ar (or another carrier gas) that is coaxially or cross-wise illuminated with a laser beam. Isotope-selective laser excitation of iQF6 molecules retards their condensation on walls and during cluster growth. This yields an isotope-enriched gas and isotope-depleted wall deposits under subsonic flow conditions and coaxial laser irradiation. Similarly, enriched QF6 gas and depleted particle clusters are formed in supercooled supersonic expansion flows that are coaxially or cross-wise irradiated. Measured isotope changes for 32SF6/34SF6 and 235UF6/238UF6 are shown to be in agreement with calculated values.

This paper describes a solid state laser concept that scales to MW levels of burst power and MJ of burst energy and burst durations measured in seconds. During lasing action, waste heat is purposely stored in the heat capacity of the active medium. The paper outlines the principal scaling laws of key operational features and arrives at a conceptual design example of the laser head as well as a mobile laser system.

A model for describing the transient molecular behavior in hot dense plasmas is presented and applied to the case of a transient F8+/F9+ molecular ion embedded in a dense (Ne ≈ 1023 cm−3) fluorine plasma. Electron screening effects on molecular energy levels and on dipolar matrix elements are investigated for specific plasma conditions. The accuracy of the calculations is tested comparing values of the polarization shift of the FLyβ line as calculated from the present model to the ones determined in the framework of the Ion Sphere Model (ISM).

Highly stable atomic frequency standards are of increasing importance for a variety of space applications, ranging from communication to navigation and time transfer to tests of fundamental science. We present a discussion of the improvements possible with laser pumping of vapor cell clocks, including applying coherent population trapping (CPT) techniques. We also present our progress toward a cold atom clock based on magneto-optically trapped atoms for space applications.

The expansion of a laser-produced plasma is studied using two computational methods and compared to experiments. The simulations and experiments were performed using a l-μxm, 600-mJ, 6-ns laser pulse. It was found that there was good agreement between the ID Lagrangian code, the snow plow model, and the experiments for our conditions.

The concept and experimental results of a microwave-excited elliptical excimer lamp are presented in this paper. The plasma excimer photons are excited at one focus, and the absorber is placed at the second focus. Two elliptical microwave cavities with different eccentricities were tested to study the excitation and characteristics of such an elliptical excimer lamp. The results show that it can be a high-efficiency, narrow-band incoherent vacuum–ultraviolet (VUV)-to-near-infrared photon source. The potential applications of such an excimer lamp, especially with tunable vibronic solid-state and diamond thin film growth, are discussed.

The evolution of thin foils accelerated over distances much greater than their in-flight thickness has been studied for a classical, low power density regime (5 × 1012 and 2 × 1013 W/cm2 at λ = 1.054 μm, 0.15 THz bandwidth). Two illumination modes have been used, one of these being based on a near-field, multi-lens array ISI smoothing, the other on focusing by F/1 aspherical lenses. The results seem to be encouraging with regard to the possibility of getting smooth, spatially uniform acceleration over distances of the order of 100 × IFFT (In-Flight-Foil Thickness). The experiments with nonsmoothed beams have shown a sort of refractive interchange stabilization for the initial on-target imprinting of the illumination non-uniformities.

The properties of heavy-ion induced fusion targets with two-sided illumination and with the converters placed completely inside the Hohlraum have been investigated using integrated simulations based on the SATURN and MIMOZA code packages in order to check the results obtained with the view-factor method in previous work, which is briefly reviewed. Separate converter simulations show the importance of an accurate treatment of radiation transport but also demonstrate that a converter efficiency of 40–80% can be achieved easily depending on the detailed converter material and geometry. For the complete target, a gas fill is shown to be necessary, and it turned out to be very important to allow some of the radiation shields to become partially transparent during the evolution. In the most favorable case, an asymmetry in the temperature on the capsule of about 5% was achieved, leading to a reduction of the neutron yield by a factor of 7 compared to an ideally symmetric situation.

The main goals of this review article are to show, on the basis of the results accumulated in this field, achievements in simulating the processes in nuclear pumped laser (NPL) active media by experiments on e-beam pumping, and to give a number of characteristic experimental examples, when this simulation has improved understanding of the inversion population processes in NPL active media (Cd+, Xe-lasers) or generated interest in experiments with fission fragments excitation (Ne-laser). In the case of the population of laser operation levels in non-equilibrium recombinating plasma, one can say with sufficient accuracy that the inversion population mechanism is identical for both excitation types.

We show through experiments of stimulated Raman scattering how solid hydrogen (parahydrogen) can open new perspectives on nonlinear optics. Two phenomena are described: One is the self-induced phase matching in parametric anti-Stokes stimulated Raman scattering (SRS) in which the phase matching is self-organized automatically without the stringent restriction of refractive-index dispersion of the medium, and the other is the extremely slow coherence decay behavior for the Raman transition that may result in the Raman width of 80 kHz full width at half maximum (FWHM).

Recent progress in laser-plasma accelerators has matured a concept of particle acceleration as a possible next-generation particle accelerator promising ultrahigh accelerating gradients in a compact size. Four major concepts of laser-plasma accelerators—the plasma beat wave accelerator, the laser wakefield accelerator, the self-modulated laser wakefield accelerator, and the plasma wakefield accelerator—are reviewed on accelerator physics issues and experiments demonstrating the basic mechanisms of their concepts. As a perspective to the future practical application, a design of 5-TeV linear colliders based on the laser wakefield accelerator is discussed.

Time- and space-integrated emission spectra measurements have been performed in plasma produced by 308 nm wavelength XeCl laser radiation (IL = (4–10)·1012 W/cm2, τ = 10 ns) and by 248 nm wavelength KrF laser pulse train radiation (IL = 5·1015 W/cm2, τ = 7 ps, 16 pulses in train) on CF2 plane target. Theoretical modelling of Lyman series and He-like ion resonance series of fluorine and its fit of experimental data show considerable differences in the absorption of laser radiation in the two plasmas.

An investigation of second harmonic (SH) and X-ray emissions from Al plasmas produced by 3-ns, 1.064-μm laser pulses at 1014 W/cm2 is reported. The SH and X-ray yields are strongly correlated as a function of the target position with respect to the laser beam focus. The SH originates from the underdense coronal plasma and has a filamentary source, while the X-ray source is uniform. The results suggest that, although the X-ray emission is significantly enhanced by the filamentation of the laser light in the corona, there is a smoothing effect in the energy transport process toward the overdense region.

Recent computer experiments on liquid Mg and Bi (and also on dense hydrogen) have focussed anew on issues involving static and dynamical structure in plasmas. In Mg and Bi, under normal liquid metal conditions, separation of core and valence electrons is valuable both for thermodynamics and in interpreting diffraction experiments. Mg is considered in some detail as a specific example where there is weak electron–ion interaction. Finally, dynamical structure is considered. After a brief summary relating back to the electron–electron pair correlation contribution in X-ray scattering, attention is next focussed on the (longitudinal) viscosity of alkali metals via the Kubo formula. This viscosity is shown to be dominated by ion–ion interactions. Nevertheless, an intimate relation at the melting point is exposed between shear viscosity, thermal conductivity, and electrical resistivity, the latter two transport coefficients being dominated by electrons.