The impact of contamination and aging effects on the long-term laser-damage resistance of SiO₂/HfO₂/TiO₂ high-reflection coatings for 1054nm

Journal Article · 16 November 2018 · Proceedings of SPIE - The International Society for Optical Engineering

DOI: https://doi.org/10.1117/12.2500279 · OSTI ID:1570279

Field, Ella Suzanne ^[1]; Kletecka, Damon E. ^[1]

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1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

The laser damage thresholds of optical coatings can degrade over time due to a variety of factors, including contamination and aging. Optical coatings deposited using electron beam evaporation are particularly susceptible to degradation due to their porous structure. In a previous study, the laser damage thresholds of optical coatings were reduced by roughly a factor of two from 2013 to 2017. The coatings in question were high reflectors for 1054 nm that contained SiO₂ and HfO₂ and/or TiO₂ layers, and they were stored in sealed PETG containers in a class 100 cleanroom with temperature control. At the time, it was not certain whether contamination or thin film aging effects were responsible for the reduced laser damage thresholds. Therefore, to better understand the role of contamination, the coatings were recleaned and the laser damage thresholds were measured again in 2018. Here, the results indicate that contamination played the most dominant role in reducing the laser damage thresholds of these optical coatings, even though they were stored in an environment that was presumed to be clean.

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC04-94AL85000
• OSTI ID: 1570279
• Report Number(s): SAND-2019-11989J; 680091
• Journal Information: Proceedings of SPIE - The International Society for Optical Engineering, Vol. 10805; ISSN 0277-786X
• Publisher: SPIECopyright Statement
• Country of Publication: United States
• Language: English