Plasma solid-density

Guethlein G, Food ME, Price D (1996) Electron temperature measurements of solid density plasmas produced by intense ultrashort laser pulses. Phys Rev Lett 77 1055-1058... 

Wharton KB, Hatchett SP, Wilks SC, Key MH, Moody JD, Yanovsky V, Offen-berger AA, Hammel BA, Perry MD, Josi C (1998) Experimental measurements of hot electrons generated by ultraintense (> 1019 W/cm2) laser-plasma interactions on solid-density targets. Phys Rev Lett 81 822-825... 

Jiang Z, Kieffer JC, Matte JP, Chaker M, Peyrusse O, Gilles D, Korn G, Mak-simchuk A, Coe S, Mourou G (1995) X-ray spectroscopy of hot solid density plasmas produced by subpicosecond high contrast laser pulses at 1018-1019 W/cm2. Phys Plasmas 2 1702-1711... 

Recent developments in ultrashort, high-peak-power laser systems, based on the chirped pulse amplification (CPA) technique, have opened up a new regime of laser-matter interactions [1,2]. The application of such laser pulses can currently yield laser peak intensities well above 1020 W cm 2 at high repetition rates [3]. One of the important features of such interactions is that the duration of the laser pulse is much shorter than the typical time scale of hydrodynamic plasma expansion, which allows isochoric heating of matter, i.e., the generation of hot plasmas at near-solid density [4], The heated region remains in this dense state for 1-2 ps before significant expansion occurs. 

Important differences also exist between plasmas and electrolyte solutions. In the latter, below the critical temperature (374°C for water), the density is not an independent variable at constant temperature, except when the system is pressurized, and even then the density can be varied only over a narrow range. Above the critical temperature, the density can be varied over a wide range by changing the volume, but, except for the work by Franck (18) and by Marshall (79), for example, on ionic conductivity, these systems are unexplored. This is particularly true for electrode and electrochemical kinetic studies. In the case of plasmas, the density may be varied under ordinary formation conditions over a wide range and, as shown in Figure 6-2, this also results in the unique feature that the temperatures of the electrons and the ions may be quite different. Another important difference between electrolytes and plasmas is the fact that free electrons exist in the latter but not in the former (an exception is liquid ammonia, in which solvated electrons can exist at appreciable concentrations). Thus, interfacial charge transfer between a conducting solid and a plasma is expected to be substantially different from that between an electrode and an electrolyte solution. The extent of these differences currently is unknown. 

Generation of broadband X-rays from a solid-density plasma with medical applications... 

It can be inferred from O Eq. (6.13) that strongly coupled plasmas tend to be cold and dense, whereas weakly coupled plasmas are diffuse and hot. Examples of strongly coupled plasmas include solid-density laser ablation plasmas, the very "cold (i.e., with kinetic temperatures similar to the ionization energy) plasmas found in "high pressure arc discharges, and the plasmas which constitute the atmospheres of collapsed objects such as white dwarfs and neutron stars. On the other hand, the hot diffuse plasmas - typically encountered in ionospheric physics, astrophysics, nuclear fusion, and space plasma physics — are invariably weakly coupled. 

Nuckols, Wood, Theisen and Zinunerman in Nature 1972 clarified in which way several groups in the USA intended to push inertial confinement /15/. In many ways the ideas mentioned in this paper were familiar to us in Frascati what came as a surprise was the aim to supercompress a Z), T plasma to densities 1000 or even 10000 times the density of D-T ice. Somehow, and for no apparent reason, the solid density ns — 5.10 ions/cm remained for a time a sort of mental barrier and although the trigger-criterion (known in its various forms since at least 1960) predicted that trigger-energy... 

Egg yolk contains mainly lipids (32 34%), proteins (16%), saccharides, mineral compounds, vitamins, dyes and water (48%). It is formed by two distinguishable fractions plasma and granules. The plasma contains mostly lipids (90% of total solids) and proteins. Granules contain mainly acidic phosphoproteins (fosvitin, lipovitellins and low-density lipoproteins), which are soluble only in higher ionic strength water solutions. 

Indeed, most of the applications of laser-plasmas rely on the efficient production of energetic electrons driven by the interaction of ultraintense laser pulses with plasmas created from solids or gases. In fact, in these interaction conditions, laser energy is efficiently transferred to electrons generating a population of so-called fast or hot electrons. The process of fast electron generation often takes place near the critical density (the density at which the laser frequency iv0 equals the local plasma frequency wpe) surface [8, 9]... 

Matter has three common states solid, liquid, and gas.There are also some far less common states, like plasma, where the electrons are separated from their atoms.The state of matter affects the properties of the material, like whether something flows or its density. The state doesn t affect the chemical makeup... 

Plasma Discharge. The low-voltage and high-current-density process in plasma gas is often called arc plasma or hot plasma. A high-power ion beam formed in the plasma flame hits the target substances to heat them to several thousand kelvins, which is enough to melt all solid materials. Under the inert gas flow, the vaporized... 

At low temperatures a pure semiconductor is a perfect insulator with no free carriers. Upon laser irradiation at a frequency greater than the semiconducting band gap, a high density of electron-hole pairs can be excited which, at liquid-helium temperatures, condense into small droplets of electron-hole plasma. These electron-hole (e-h) droplets have been discussed thoroughly in a dedicated volume of Solid State Physics that contains reviews of theoretical aspects (Rice, 1977) and experiments (Hensel et al., 1977). 

The pursuit of further miniaturization of dectronic circuits has made submicrometer resolution lithography a crucial dement in future computer engineering. LB films have long been considered potential candidates for resist applications, because conventional spin-coated photoresist materials have large pinhole densities and variations of thickness. In contrast, LB films are two-dimensional, layered, crystalline solids that provide high control of film thickness and are impermeable to plasma down to a thickness of 40 nm (46). The electron beam polymerization of (Q-tricosenoic acid monolayers has been mentioned. Another monomeric amphiphile used in an attempt to develop dectron-beam-resist materials is a-octadecylacryhc acid (8). 

At low pressures, the electron temperature is much higher than the temperature of the gas. The temperature of an electron with energy of 2 eV will be 23,200 K. Even though the individual electrons are very hot, the system or gas remains at ambient temperature. Because of the very low density and very low heat capacity of the electrons, the amount of heat transferred to the gas and to the walls of the container is very small. Thus the term cold plasma derives its meaning from the small amount of heat transferred to the gas or solids in contact with it. 

Electrodes or Langmuir probes may be inserted into plasmas that are large enough (>1 cm) and relatively cool (<104 K). The net current to the probe is measured as a function of the applied voltage. Electron temperatures, electron and ion densities, and space and wall potentials may be derived from the probe signals. Interaction of plasmas with solid probes tends to perturb plasma conditions. 

Auger emission to neutralize incoming ions leaves the solid surface in an excited state relaxation of the surface results in secondary electron generation (23, 24). Secondary electrons are ejected when high-energy ions, electrons, or neutral species strike the solid surface. These electrons enhance the electron density in the plasma and can alter the plasma chemistry near a solid surface. Radiation impingement on a surface can induce a number of phenomena that depend upon the bombardment flux and energy. 

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