Photoelectron spectroscopic investigations (XPS) of the spinels NiMn2O4 and MzNiMn2−zO4 (M = Li, Cu) in comparison with Mn2TiO4, ZnMn2O4, and MgNiMnO4, containing Mn in only one oxidation state, show that in the former compounds MnII, MnIII, and MnIV are present. By a fitting process yielding the amounts of the Mn ions in the different oxidation states it is possible to determine the cation distribution of NiMn2O4 which is characterized by a high inversion parameter and a considerable degree of disproportionation. Cation valencies and their distribution in the substituted spinels are discussed. An increasing concentration of MnIV with higher values of z is reflected in the spectra by shift of the Mn p signals and by changes in their shape.

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.

The laser damage thresholds (LDT) of optical coatings lie, as a rule, markedly below those of the respective bulk materials. This is due to diverse specific realstructure properties with regard to composition, crystallography, microstructure and the physico-chemical structure of the interfaces. These properties depend in a highly complex and sensitive way on the substrate treatment, coating techniques and deposition conditions. With evaporated and sputtered oxide coatings as example, some correlations between structural thin film properties (e.g. crystallography, microstructure, anisotropy, chemical composition, defects) and the ultraviolet (248 nm) or near infrared (1064 nm) laser damage thresholds are discussed with concern to a further increase of the damage resistance. It is evident from data that an approach to the problem requires complex investigations ofthe technology-structure-properties relationships.

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Micro and nano optics enable the control of light for producing intensity distributions with given profiles, propagation properties and polarization states. The higher the requirements on the optical function, the more complicated will be its realizing with a single element surface or a single element class. Combinations of refractive and diffractive, both diffractive or sub-wavelength structures with each other give the ability to link the advantages of different element classes or different element functions for realizing the optical functionality. In the paper we discuss two different examples of combinations for DUV applications. In detail we present a diffractive -diffractive beam homogenizer with NA of 0.3 that show no zero order. A binary phase grating for polarization control combined with a beam shaping element will be presented. The polarized order of this grating shows an efficiency of about 90% with a degree of polarization better than 90%. Wave optical and rigorous design strategies and simulations as well as the optical measurements will be discussed for the given examples.