Sculptured thin film based all-silica mirrors for high power lasers

Optical components are the main parts in laser systems, which limits the total generated output power due to laser-induced damage. At nanosecond laser pulses materials experiences thermal expansion phenomena, therefore optical coatings gain stress leading to breakdown. Moreover, the main resistance to laser radiation is limited by material itself (band gap). Glancing angle deposition method is presented to produce porous nanostructured coatings, which are characterized by low inner stress. Optical resistivity dependance on porosity of several materials such as aluminium, niobium and silicium oxides singlelayers was evaluated. Furthermore, all-silica Bragg mirror is formed and optical properties investigated in different environments to achieve stable and superior optical resistance.