The research on two-color photon sources in infrared and X-ray ranges by compton scattering

The generation of a two-color source of FEL light in both the infrared and soft X-ray ranges by intracavity Compton backscattering is demonstrated by the Beijing FEL facility. 1.20–1.35 keV soft X-rays are successfully extracted from the optical cavity of the FEL through a porous metallic mirror, while a 9–10 μm FEL laser is output in the other dielectric mirror simultaneously. The average output flux of X-ray is 102–103 photons/s when the average output FEL laser power is 6–20 mW. The experimental result allows us to envision a convenient way to expand the application areas of IR FEL facilities into X-ray or γ-ray ranges.