Potential Characteristics and Applications of X-Ray Lasers,

This is primarily a limited review lof research on X-ray lasers and of the applications which may be possible when a source is available which emits short, monochromatic and intense pulses as coherent X-rays. Some of the progress toward producing short-wavelength coherent radiation, either by direct laser action or by frequency manipulation, is summarized. Reports of X-ray laser action and spectroscopic evidence for relevant population inversions are discussed. Potential X-ray laser characteristics, which are derived from the work to date and which will determine applications, are discussed. Included is a comparison with two other bright X-ray sources, namely multi-million degree plasma and GeV electron storage rings. One section is concerned with the heating which will occur when an X-ray laser pulse strikes condensed matter. A simple calculational technique and some results are given there. Possible areas of X-ray laser usage are reviewed. The final section discusses geometries which may be favorable for production of X-ray laser action, and multi-layer reflectors which may make possible short-wavelengths resonators.