Investigations in fs-laser damage mechanisms within the recent years indicate that damage mechanisms in the fs-range are based on electronic interaction schemes in the material. Usually, a direct correlation of the power handling capability to the band gap structure of the material and the field strength distribution in the optical system is observed. The present work is focused on the optimization of high refractive index coating materials by mixing with silica. The different compositions of mixed materials are manufactured with an IBS coating process using a zone target. This technique allows for a continuous variation of the material composition. In addition, new coating designs were developed to adapt the contents of silica within the layers to the high field strengths. By combining these techniques a significant increase of the laser damage threshold could be accomplished.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.