Reverse guide field free electron laser

摘要

An electromagnetic radiation amplification device comprising an electron gun for introducing a stream of electrons into an electron drift tube/wavequide in which an axial magnetic field and a wiggler magnetic field have been induced to impart a helical gyration to the electrons as they travel parallel to the tube. The axial, or guide, magnetic field is directed in the direction opposite to the direction of propagation of the electrons if the electrons have a right handed helical gyration and is directed in the direction of propagation of the electrons if the electrons have a left handed helical gyration.