Abstract: A free-electron laser capable of operation at a shorter wavelength than the fundamental lasing wavelength, but without any increase in electron energy requirements. The laser includes a conventional high-energy electron beam source and a wiggler transverse magnetic field through which the beam is passed to produce lasing. Opposed optical mirrors are selected to be reflective at a selected harmonic wavelength as well as at the fundamental wavelength. Lasing is initiated at the fundamental wavelength, but is then supported at the selected harmonic wavelength as well. By appropriate design lasing at the fundamental wavelength may be subsequently terminated without affecting lasing at the harmonic wavelength, which continues at a substantially reduced energy cost than would have been incurred if lasing at the harmonic frequency been initiated in a fundamental mode.

Abstract: A method for decelerating beams of charged particles that have been accelerated using a linear accelerator. The high-energy particles, such as electrons, are passed through a series of induction cells, each of which generates an electrical pulse as a packet of electrons passes through it and has its velocity reduced. The energy removed from the packets of electrons in the form of electrical pulses can either be stored for later use or discharge, or can be immediately employed to accelerate other electrons in an associated linear accelerator.

Abstract: A plasma focus electrode is described which utilizes a cylindrical hollow conductive anode having a concentric cylindrical insulator. This anode is used in conjunction with a lithium vortex cathode in the formation of a plasma focus for the liberation of neutrons from a plasma at the focus.