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Title: Interference effects in laser-induced plasma emission from surface-bound metal micro-particles

Abstract

Here, the light-matter interaction of an optical beam and metal micro-particulates at the vicinity of an optical substrate surface is critical to the many fields of applied optics. Examples of impacted fields are laser-induced damage in high power laser systems, sub-wavelength laser machining of transmissive materials, and laser-target interaction in directed energy applications. We present a full-wave-based model that predicts the laser-induced plasma pressure exerted on a substrate surface as a result of light absorption in surface-bound micron-scale metal particles. The model predictions agree with experimental observation of laser-induced shallow pits, formed by plasma emission and etching from surface-bound metal micro-particulates. It provides an explanation for the prototypical side lobes observed along the pit profile, as well as for the dependence of the pit shape on the incident laser and particle parameters. Furthermore, the model highlights the significance of the interference of the incident light in the open cavity geometry formed between the micro-particle and the substrate in the resulting pit shape.

Authors:
 [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:
1366957
Report Number(s):
LLNL-JRNL-723532
Journal ID: ISSN 1094-4087; OPEXFF
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Optics Express
Additional Journal Information:
Journal Volume: 25; Journal Issue: 9; Journal ID: ISSN 1094-4087
Publisher:
Optical Society of America (OSA)
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 70 PLASMA PHYSICS AND FUSION; Laser damage; Optics at surfaces; Optical materials; Scattering; Laser materials processing

Citation Formats

Feigenbaum, Eyal, Malik, Omer, Rubenchik, Alexander M., and Matthews, Manyalibo J. Interference effects in laser-induced plasma emission from surface-bound metal micro-particles. United States: N. p., 2017. Web. doi:10.1364/OE.25.009778.
Feigenbaum, Eyal, Malik, Omer, Rubenchik, Alexander M., & Matthews, Manyalibo J. Interference effects in laser-induced plasma emission from surface-bound metal micro-particles. United States. doi:10.1364/OE.25.009778.
Feigenbaum, Eyal, Malik, Omer, Rubenchik, Alexander M., and Matthews, Manyalibo J. Wed . "Interference effects in laser-induced plasma emission from surface-bound metal micro-particles". United States. doi:10.1364/OE.25.009778. https://www.osti.gov/servlets/purl/1366957.
@article{osti_1366957,
title = {Interference effects in laser-induced plasma emission from surface-bound metal micro-particles},
author = {Feigenbaum, Eyal and Malik, Omer and Rubenchik, Alexander M. and Matthews, Manyalibo J.},
abstractNote = {Here, the light-matter interaction of an optical beam and metal micro-particulates at the vicinity of an optical substrate surface is critical to the many fields of applied optics. Examples of impacted fields are laser-induced damage in high power laser systems, sub-wavelength laser machining of transmissive materials, and laser-target interaction in directed energy applications. We present a full-wave-based model that predicts the laser-induced plasma pressure exerted on a substrate surface as a result of light absorption in surface-bound micron-scale metal particles. The model predictions agree with experimental observation of laser-induced shallow pits, formed by plasma emission and etching from surface-bound metal micro-particulates. It provides an explanation for the prototypical side lobes observed along the pit profile, as well as for the dependence of the pit shape on the incident laser and particle parameters. Furthermore, the model highlights the significance of the interference of the incident light in the open cavity geometry formed between the micro-particle and the substrate in the resulting pit shape.},
doi = {10.1364/OE.25.009778},
journal = {Optics Express},
number = 9,
volume = 25,
place = {United States},
year = {Wed Apr 19 00:00:00 EDT 2017},
month = {Wed Apr 19 00:00:00 EDT 2017}
}

Journal Article:
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