Soft-x-ray spectroscopy of subpicosecond laser-produced plasmas

Experiments that examine the interaction of high-intensity subpicosecond laser radiation (∼1018 W/cm2) with solid targets are performed. Soft-x-ray spectra from interactions with Teflon and aluminum targets that imply the creation of high-temperature (approx-gt 200 eV) high-density (approx-gt 1023 cm-3) plasmas are obtained. Effects of a prepulse on the plasma characteristics are examined. The applicability of short, intense laser pulses for the formation of population inversions on x-ray transitions during recombination of high-density plasmas is discussed. copyright 1996 Optical Society of America