title: Light intensification modeling of coating inclusions irradiated at 351 and 1053 nm.
abstract: Electric-field modeling provides insight into the laser damage resistance potential of nodular defects. The laser-induced damage threshold for high-reflector coatings is 13x lower at the third harmonic (351 nm) than at the first harmonic (1053 nm) wavelength. Linear and multiphoton absorption increases with decreasing wavelength, leading to a lower-third harmonic laser resistance. Electric-field effects can also be a contributing mechanism to the lower laser resistance with decreasing wavelength. For suitably large inclusions, the nodule behaves as a microlens. The diffraction-limited spot size decreases with wavelength, resulting in an increase in intensity. Comparison of electric-field finite-element simulations illustrates a 3x to 16x greater light intensification at the shorter wavelength.
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550, USA. stolz1@llnl.gov
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Stolz
authors.forename: Scott
authors.initials: S
authors.lastname: Hafeman
authors.forename: Thomas V
authors.initials: TV
authors.lastname: Pistor