Studies of plasmas excited by intense subpicosecond radiation for x-ray generation

The use of recently developed high brightness subpicosecond lasers for the study of the interaction of solid matter is leading to the production of powerful incoherent x-ray sources associated with dense plasma environments. The use of these intense pulsed x-ray sources will enable the production of extremely high densities and levels of electronic excitation in materials while leaving the system kinetically cold during the interaction. This general condition is extremely conducive to the amplification of short wavelength radiation. The analysis of a particular case for amplification at a quantum energy of ∼ 1 keV indicates that a total energy of ∼ 1 J of ultraviolet radiation is necessary for excitation. The control of this class of physical processes is expected to lead to a new generation of amplifiers in the x-ray range.