title: Onset of the optical damage in CaF(2) optics caused by deep-UV lasers.
abstract: The exterior sides of calcium fluoride (CaF(2)) outcoupling mirrors are damaged by ArF laser light irradiation with high pulse-energy densities (80 mJ/cm(2)). The damage is generated by a partial alteration of the CaF(2) substrate to calcite. The CaF(2) decomposition is driven by photochemical processes due to the UV light and the presence of water vapor and is supported by elevated temperatures within the laser beam transmitting area. Small filaments act as starting points for the decomposition process, where kerogenous carbon and calcite can occur.
authors.affiliation: Center for NanoScience (CeNS) and Department of Earth and Environmental Sciences,Ludwig-Maximilians-Universität München, Theresienstrasse 41, 80333 Munich, Germany. michael.bauer@lrz.uni-muenchen.de
authors.forename: Michael
authors.initials: M
authors.lastname: Bauer
authors.forename: Martin
authors.initials: M
authors.lastname: Bischoff
authors.forename: Thomas
authors.initials: T
authors.lastname: Hülsenbusch
authors.forename: Ansgar
authors.initials: A
authors.lastname: Matern
authors.forename: Robert W
authors.initials: RW
authors.lastname: Stark
authors.forename: Norbert
authors.initials: N
authors.lastname: Kaiser