Working with wavelengths shorter than the deep ultraviolet involves the development of dedicated optics for free-electron lasers with devoted coating techniques and characterizations. High-performance deep-ultraviolet optics are specially developed to create low-loss, high-reflectivity dielectric mirrors with long lifetimes in harsh synchrotron radiation environments. In February 2001, lasing at 189.7 nm, the shortest wavelength obtained so far with free-electron-laser oscillators, was obtained at the European Free-electron-laser project at ELETTRA Synchrotron Light Laboratory, Trieste, Italy. In July 2001, 330-mW extracted power at 250 nm was measured with optimized transmission mirrors. Research and development of coatings correlated to lasing performance are reported.
© 2002 Optical Society of America
(220.0220) Optical design and fabrication : Optical design and fabrication
(310.3840) Thin films : Materials and process characterization
(310.6860) Thin films : Thin films, optical properties
Alexandre Gatto, Roland Thielsch, Joerg Heber, Norbert Kaiser, Detlev Ristau, Stephan Günster, Juergen Kohlhaas, Marino Marsi, Mauro Trovò, Richard Walker, David Garzella, Marie Emmanuelle Couprie, Philippe Torchio, Marco Alvisi, and Claude Amra, "High-Performance Deep-Ultraviolet Optics for Free-Electron Lasers," Appl. Opt. 41, 3236-3241 (2002)