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In this work we present a short review of SXR and EUV optics that have been designed and developed for experiments concerning material processing and imaging, using a laser-plasma radiation source based on a gas puff target. Three different kinds of mirrors employed as the EUV collectors are presented: the grazing incidence axisymmetrical ellipsoidal mirror, the grazing incidence multifoil mirror, and the ellipsoidal mirror with Mo/Si multilayer coating. Experiments concerning characterization of the mirrors were performed using EUV radiation from Kr or Xe plasmas produced in a double stream gas puff target irradiated with Nd:YAG laser pulses (4ns, 0.8 J, 10 Hz). Intensity of the focused radiation was sufficient for micromachining of organic polymers and surface modification of organic and inorganic solids. Different kinds of micro-and nanostructures created in near-surface layers of different kinds polymers were obtained. Significant differences were revealed in XPS spectra acquired for irradiated and not irradiated polymers.

High resolution imaging methods and techniques are currently under development. One of them is an extreme ultraviolet (EUV) microscopy, based on Fresnel zone plates. In this paper a compact, high-repetition, laser-plasma EUV source, emitting quasi-monochromatic radiation at 13.8nm wavelength was used in a desktop EUV transmission microscopy with a spatial (half-pitch) resolution of 50nm. EUV microscopy images of objects with various thicknesses and the spatial resolution measurements using the knife-edge test are presented.

By traveling wave irradiation with a compact, 2‐beam, 1‐ps, 20‐J CPA Nd‐glass laser dedicated to x‐ray laser research, saturated amplification has been demonstrated in Ni‐like Ag at 13.9 nm and Ni‐like Sn at 12.0 nm. High gain amplification has been also obtained in Ni‐like La at 8.8 nm and with gaseous targets in Ne‐like Ar at 46.9 nm and Ni‐like Xe at 9.98 nm. Generation of highly coherent x‐ray laser is planned by injection seeding of the plasma amplifier. The newly developed 340‐TW Ti‐sapphire laser may enable generating exceedingly high power x‐ray radiation which will be useful for pumping inner‐shell ionization x‐ray lasers.

We report the first X‐ray laser experiments with the use of laser‐irradiated gas puff targets. The targets, produced by pulsed injection of a small amount of gas from a high‐pressure solenoid valve through a nozzle in a form of a slit, has been characterized by optical interferometry and X‐ray backlighting. The formation of elongated hot plasma columns up to 30‐mm long is demonstrated. The spatial uniformity of the column was monitored by means of an X‐ray pinhole camera. XUV spectra measurements for SF6 gas puff targets show predominant 3–2 line of hydrogenic fluorine (λ=8.1 nm), however, only linear increasing of its intensity with the target length was observed. An inversion on the lithium‐like 4d‐3p line can be inferred from the relative intensities of the Li‐like resonance lines. Results for Kr target indicate that the plasma temperature was too low to create Ne‐like ions.