induced by the pump beam, which is related to the charge transfer caused by the excitation of a specific atom. The technique promises information about the atomic identity of laser-excited intrinsic and defect states that is difficult if not impossible to obtain by any other technique. Current efforts are directed toward testing whether or not this concept is feasible.
Modern third-generation synchrotrons will cover the vacuum ultraviolet and extended ultraviolet regions well and will provide opportunities to explore much new scientific research in this wavelength region.
There are currently no free electron lasers that operate in this region. The construction of a device should be possible with some additional research and development. It may be possible to construct a large VUV free electron laser facility now, since most of the component pieces have been demonstrated, but construction of a VUV free electron laser using current technology would cost on the order of tens of millions of dollars and involve some risk.
A user community for a VUV free electron laser is not well developed at this time but could grow with the exploition of third-generation synchrotron sources, demonstrating proof-of-principle experiments.
Scientific opportunities in the vacuum ultraviolet and extended ultraviolet wavelength range should be explored by the use of existing synchrotron sources.
The development of technology for a vacuum ultraviolet free electron laser should be supported. Among the goals of this development should be lowering the cost of these devices and increasing their reliability.
A free electron laser user facility in the vacuum ultraviolet should not be constructed at the present time. The scientific case for a VUV free electron laser facility does not justify the current cost, and the technology is not sufficiently well developed.
Kortright, J.B. 1990. Chapter 13 in Free Electron Laser Handbook. W.B.Colson, C. Pellegrini, and A. Renieri, eds. The Netherlands: North-Holland Physics, Elsevier Science Publishing Co.