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Interactions of high-intensity femtosecond lasers with deuterium clusters leading to Coulombic explosions and subsequent production of fusion neutrons attracted in recent years considerable attention. In order to maximize the neutron yield finding a dependence of clusters size and their spatial distribution on experimental conditions became very important. In this paper a possibility to measure the deuterium clusters spatial distributions experimentally was analyzed. In combination with experiments recently performed in the Laboratory of Quantum Optics at the Korea Atomic Energy Research Institute (KAERI) interferometry was identified as the diagnostics suitable for such measurements.

Laser produced plasma is one of the brilliant x-ray source that has unique capabilities for use in a wide range of science. Here we describe two examples of laser-produced plasma x-ray source application; one is for the semiconductor device industry and the other is for the astronomy. Extreme ultraviolet (EUV) light sources for microlithography are receiving much attention as an industrial application of laser-produced x-ray source. High power and clean EUV light source, 13.5 nm of wavelength, is developed for mass-production of next generation semiconductor devices. Highest EUV conversion efficiency of 4% has been attained by using low-density and minimum-mass tin targets produced by laser-driven explosion of micro-droplet. In addition, it was recently demonstrated that laser-produced x-ray source is very useful to simulate x-ray astronomical phenomena in the laboratory. A 0.5-keV Planckian x-ray source was created with laser driven implosion for producing non-local-thermodynamical-equilibrium (non-LTE) photoionized plasmas, which is a key to understand astronomical compact objects. Laboratory experiment of non-LTE photoionized plasma offers novel test bed for validation and verification of computational codes used in x-ray astronomy.

Photo-ionized silicon plasma was studied using 500-eV Planckian radiation from implosion core plasma generated with Gekko-XII laser to simulate a astrophysical photo-ionized plasma. Three major features were observed in an energy range from 1.80 to 1.88 keV and origins of the features were replicated with a time-dependent collisional-radiative model including photo-ionization processes: The line at 1.865 keV is the resonance line by inner-shell photo-ionization of Li-like Si ions and that at 1.840 keV is the sum of satellite lines attributed to the inner-shell photo-ionization of Be-like ions. Emission lines in the soft x-ray/extreme ultra-violet (EUV) region (i.e., 140 to 300 eV) from the low-temperature Si plasma in prior to the photo-ionization were also identified to extract the intial temperature and density of the pre-formed Si.