Design and fabrication of a novel high damage threshold HfO2/TiO2/SiO2 multilayer laser mirror

Abstract:

This paper describes a new method to design a laser mirror with high reflectivity, wide reflection bandwidth and high laserinduced damage threshold. The mirror is constructed by three materials of HfO₂/TiO₂/SiO₂ based on electric field and temperature field distribution characteristics of all-dielectric laser high reflector. TiO₂/SiO₂ stacks act as the high reflector (HR) and broaden the reflection bandwidth, while HfO₂/SiO₂ stacks are used for increasing the laser resistance. The HfO₂/TiO₂/SiO₂ laser mirror with 34 layers is fabricated by a novel remote plasma sputtering deposition. The damage threshold of zero damage probability for the new mirror is up to 39.6 J/cm² (1064 nm, 12 ns). The possible laser damage mechanism of the mirror is discussed.