Investigation of optical coatings light losses in laser systems

Optical coatings are one of the main areas of research for advanced laser systems. With high-power radiation, thin films on optical components limit overall system capabilities. In order to further successfully develop laser systems, comprehensive thin film light losses testing is required to increase the overall quality of the optical components. During the doctoral studies it is planned to carry out complex studies, during which optical coatings will be formed for laser systems. The main purpose of the research is to investigate the dependence of light losses on thin film deposition conditions. For this purpose, modern laser systems will be used to measure the absorption of material on the basis of photo-thermal effects, optical resistance to laser radiation, and so on. The aim is to analyze the correlations between losses, optical resistance and material properties. This will be done by depositing mixes and changing their composition. Such studies have not yet been carried out.
Successful results will be used for the formation and further investigation of multilayer coatings with high resistance and low optical losses.
Work will be carried out at the Optical Coatings Laboratory. It has five thin film deposition devices (two sputtering units, two evaporation and one atomic layer deposition). Each of them can synthesize oxides, nitrides, metals, fluorides and their mixtures. The laboratory also has advanced measuring and analysis equipment: spectrophotometer, atomic force microscope, laser set-up for measuring damage threshold and absorption coefficient, and so on.
Each of these devices has applied in research for several years. Technology for mixes formation and its research in the laboratory have been proceeded for about ten years. Five articles on this topic were published during this period. The laboratory also carries out various types of project activities in the field of materials mixing technologies and their use in the formation of low-loss optical components. At present, the laboratory has a technology for coating mixtures, but there is no comprehensive research on the dependence of optical losses on the composition of the mixture and the reasons for that dependence.
For more information, please contact the theme supervisor T. Tolenis.