Free-electron laser

Topic

A free-electron laser (FEL) is a fourth-generation light source that produces extremely brilliant and short pulses of radiation. Unlike conventional lasers that rely on stimulated emission from bound atomic or molecular states, an FEL utilizes a relativistic electron beam moving freely through a magnetic structure as its gain medium. This allows the laser to be widely tunable across a broad range of wavelengths, from microwaves to X-rays.