Comparison of Single-Layer and Double-Layer Anti-Reflection Coatings Using Laser-Induced Damage Threshold and Photothermal Common-Path Interferometry

Abstract

Abstract:The dielectric thin-film coating on high-power optical components is often the weakest region and will fail at elevated optical fluences. A comparison of single-layer coatings of ZrO 2 , LiF, Ta 2 O 5 , SiN, and SiO 2 along with anti-reflection (AR) coatings optimized at 1064 nm comprised of ZrO 2 and Ta 2 O 5 was made, and the results of photothermal common-path interferometry (PCI) and a laser-induced damage threshold (LIDT) are presented here. The coatings were grown by radio frequency (RF) sputtering, pulsed direct-current (DC) sputtering, ion-assisted electron beam evaporation (IAD), and thermal evaporation. Test regimes for LIDT used pulse durations of 9.6 ns at 100 Hz for 1000-on-1 and 1-on-1 regimes at 1064 nm for single-layer and AR coatings, and 20 ns at 20 Hz for a 200-on-1 regime to compare the //ZrO 2 /SiO 2 AR coating.

Comparative study of dielectric coating materials for micro-cavity applications

“…A further experimental study will be made to compare the absorption losses for multilayer stacks to the absorptance calculated from the spectral characterization. Many techniques such as the photothermal deflection technique [65], the photothermal common path interferometry [66,67] and lock-in detection [68] allow the accurate measurement of very small absorption losses. High reflectivity mirrors for quantum communication applications usually require surface roughness between 0.2 nm and 0.3 nm in order to reduce the scatter losses [60].…”

Development of Wide-Angle Depolarizing Reflector at 1064 nm

“…The weak absorption of thin films was measured by a photothermal weak absorption meter PCI-03 manufactured by SPTS [ 23 ]. Figure S1 shows the working principle of the self-built photothermal co-routing technology.…”