E. Eva
K. Mann
N. Kaiser
B. Anton
R. Henking
D. Ristau
P. Weissbrodt
D. Mademann
L. Raupach
E. J. Hacker

Laser conditioning of LaF3/MgF2 dielectric coatings at 248 nm

Applied Optics
28
35
5613-5619
1996
Type: Zeitschriftenaufsatz (non-reviewed)
Abstract
Highly reflective LaF(3)/MgF(2) systems for a wavelength of 248 nm on MgF(2) and crystalline quartz substrates were investigated. The influence of laser conditioning on damage threshold and absorptance was remarkable in those coatings that had a high initial absorptance. Monitoring with a laser calorimeter revealed the conditioning effect to be a function of the irradiation dose rather than of energy density or pulse rate. Furthermore, x-ray photoelectron spectroscopy and transmission electron microscopy investigations showed that conditioning induces stoichiometric and structural changes in the multilayers, especially in near-surface sublayers, whereas scanning electron microscopy and atomic force microscopy investigations indicated that the surface remains unchanged.