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Title: Laser-induced damage of intrinsic and extrinsic defects by picosecond pulses on multilayer dielectric coatings for petawatt-class lasers

Abstract

Here, we describe a damage testing system and its use in investigating laser-induced optical damage initiated by both intrinsic and extrinsic precursors on multilayer dielectric coatings suitable for use in high-energy, large-aperture petawatt-class lasers. We employ small-area damage test methodologies to evaluate the intrinsic damage resistance of various coatings as a function of deposition methods and coating materials under simulated use conditions. In addition, we demonstrate that damage initiation by raster scanning at lower fluences and growth threshold testing are required to probe the density of extrinsic defects, which will limit large-aperture optics performance.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1289365
Report Number(s):
LLNL-JRNL-690959
Journal ID: ISSN 0091-3286
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Optical Engineering
Additional Journal Information:
Journal Volume: 56; Journal Issue: 1; Journal ID: ISSN 0091-3286
Publisher:
SPIE
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 42 ENGINEERING; laser-induced damage; multilayer dielectric coatings; coating defects; picosecond pulses; petawatt lasers; pulsed laser-matter interactions

Citation Formats

Negres, Raluca A., Carr, Christopher W., Laurence, Ted A., Stanion, Ken, Guss, Gabe, Cross, David A., Wegner, Paul J., and Stolz, Christopher J. Laser-induced damage of intrinsic and extrinsic defects by picosecond pulses on multilayer dielectric coatings for petawatt-class lasers. United States: N. p., 2016. Web. doi:10.1117/1.OE.56.1.011008.
Negres, Raluca A., Carr, Christopher W., Laurence, Ted A., Stanion, Ken, Guss, Gabe, Cross, David A., Wegner, Paul J., & Stolz, Christopher J. Laser-induced damage of intrinsic and extrinsic defects by picosecond pulses on multilayer dielectric coatings for petawatt-class lasers. United States. doi:10.1117/1.OE.56.1.011008.
Negres, Raluca A., Carr, Christopher W., Laurence, Ted A., Stanion, Ken, Guss, Gabe, Cross, David A., Wegner, Paul J., and Stolz, Christopher J. 2016. "Laser-induced damage of intrinsic and extrinsic defects by picosecond pulses on multilayer dielectric coatings for petawatt-class lasers". United States. doi:10.1117/1.OE.56.1.011008. https://www.osti.gov/servlets/purl/1289365.
@article{osti_1289365,
title = {Laser-induced damage of intrinsic and extrinsic defects by picosecond pulses on multilayer dielectric coatings for petawatt-class lasers},
author = {Negres, Raluca A. and Carr, Christopher W. and Laurence, Ted A. and Stanion, Ken and Guss, Gabe and Cross, David A. and Wegner, Paul J. and Stolz, Christopher J.},
abstractNote = {Here, we describe a damage testing system and its use in investigating laser-induced optical damage initiated by both intrinsic and extrinsic precursors on multilayer dielectric coatings suitable for use in high-energy, large-aperture petawatt-class lasers. We employ small-area damage test methodologies to evaluate the intrinsic damage resistance of various coatings as a function of deposition methods and coating materials under simulated use conditions. In addition, we demonstrate that damage initiation by raster scanning at lower fluences and growth threshold testing are required to probe the density of extrinsic defects, which will limit large-aperture optics performance.},
doi = {10.1117/1.OE.56.1.011008},
journal = {Optical Engineering},
number = 1,
volume = 56,
place = {United States},
year = 2016,
month = 8
}

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Free Publicly Available Full Text
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  • Laser-induced damage with ps pulse widths straddles the transition from intrinsic, multi-photon ionization and avalanche ionization-based ablation with fs pulses to defect-dominated, thermal-based damage with ns pulses. We investigated the morphology of damage for fused silica and silica coatings between 1 ps and 60 ps at 1053 nm. Using calibrated laser-induced damage experiments, in situ imaging, and high-resolution optical microscopy, atomic force microscopy, and scanning electron microscopy, we show that defects play an important role in laser-induced damage down to 1 ps. Three types of damage are observed: ablation craters, ultra-high density pits, and smooth, circular depressions with central pits.more » For 10 ps and longer, the smooth, circular depressions limit the damage performance of fused silica and silica coatings. The observed high-density pits and material removal down to 3 ps indicate that variations in surface properties limit the laser-induced damage onset to a greater extent than expected below 60 ps. Below 3 ps, damage craters are smoother although there is still evidence as seen by AFM of inhomogeneous laser-induced damage response very near the damage onset. These results show that modeling the damage onset only as a function of pulse width does not capture the convoluted processes leading to laser induced damage with ps pulses. It is necessary to account for the effects of defects on the processes leading to laser-induced damage. In conclusion, the effects of isolated defects or inhomogeneities are most pronounced above 3 ps but are still discernible and possibly important down to the shortest pulse width investigated here.« less
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