A survey of biophysical and biomedical applications of free-electron lasers (FELs) is
presented. FELs are pulsed light sources, collectively operating from the microwave through
the x-ray range. This accelerator-based technology spans gaps in wavelength, pulse
structure, and optical power left by conventional sources. FELs are continuously tunable and
can produce high-average and high-peak power. Collectively, FEL pulses range from
quasicontinuous to subpicosecond, in some cases with complex superpulse structures. Any …