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Abstract: The TiO x thin films were prepared by electron beam evaporation using TiO as the starting material. The effect of the annealing temperature on the optical and electrical properties was investigated. The spectra of X-ray photoelectron spectroscopy reveal that Ti in the films mainly exist in the forms of Ti2+ and Ti3+ below 400°C 24h annealing. The charge transfer between different titanium ion contribute greatly to the color, absorption, and electrical resistance of the films. [Copyright &y& Elsevier]

Abstract: The laser-induced damage of Ta2O5 films annealed at a wide range of temperature (473–1273K) at the laser wavelengths of 1064 and 355nm was investigated. The relations between microstructure, optical properties, chemical composition, absorption and laser-induced damage threshold (LIDT) were studied. The dependence of a damage mechanism on laser wavelengths was discussed. It was found that the LIDT either at 1064 or 355nm first increased and then decreased with increase of annealing temperature. The LIDT at 1064nm was influenced by the substoichiometric defects, structural defects and thermal diffusion, whereas at 355nm it was affected mainly by the intrinsic absorption and structural defects. Both the maximum LIDT at the two wavelengths were obtained at the annealing temperature of 873K, which could be attributed to the lowest defect density in films. [Copyright &y& Elsevier]

Abstract: With the present work we tried to study the effective methods to improve the laser-induced damage threshold (LIDT) and reflectance of HR coatings at 355nm. The work presented in this paper was part of an ongoing study about vacuum annealing. It was dedicated to study the effects of vacuum annealing with different temperature gradients on the structure, optical properties and laser-induced damage threshold (LIDT) of 355nm Al2O3/MgF2HR coatings. A number of samples were prepared by electron beam evaporation using the same deposition process with an optimal deposition temperature of 280°C. After deposition, samples were annealed in the coating chamber for 3h with different temperature gradients. Morphologies of the samples were observed by Leica-DMRXE Microscope. Structure of the samples had been characterized by X-ray diffraction (XRD). Transmittance and reflectance of the samples were measured by Lambda 900 Spectrometer. The LIDT of the samples was measured by a 355nm Nd:YAG laser with a pulse width of 8ns. It was found that the temperature gradient of vacuum annealing had significant effects on the morphology, structure, absorption, and LIDT of the samples. [Copyright &y& Elsevier]