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Title: An improved three-dimensional two-temperature model for multi-pulse femtosecond laser ablation of aluminum

Abstract

In this paper, an improved three-dimensional two-temperature model for multi-pulse femtosecond laser ablation of aluminum was proposed and proved in our experiment. Aiming to achieve hole-drilling with a high ratio of depth/entrance diameter in vacuum, this model can predict the depth and radius of the drilled holes precisely when employing different laser parameters. Additionally, for multi-pulse laser ablation, we found that the laser fluence and number of pulses are the dominant parameters and the multi-pulse ablation threshold is much lower than the single-pulse one, which will help to obtain high-quality holes.

Authors:
; ; ;  [1]
  1. State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China)
Publication Date:
OSTI Identifier:
22413080
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABLATION; ALUMINIUM; BOREHOLES; LASER DRILLING; LASER RADIATION; MATHEMATICAL MODELS; PULSED IRRADIATION; TEMPERATURE DEPENDENCE; THREE-DIMENSIONAL LATTICES

Citation Formats

Zhang, Jinping, Chen, Yuping, E-mail: ypchen@sjtu.edu.cn, Hu, Mengning, and Chen, Xianfeng. An improved three-dimensional two-temperature model for multi-pulse femtosecond laser ablation of aluminum. United States: N. p., 2015. Web. doi:10.1063/1.4907990.
Zhang, Jinping, Chen, Yuping, E-mail: ypchen@sjtu.edu.cn, Hu, Mengning, & Chen, Xianfeng. An improved three-dimensional two-temperature model for multi-pulse femtosecond laser ablation of aluminum. United States. doi:10.1063/1.4907990.
Zhang, Jinping, Chen, Yuping, E-mail: ypchen@sjtu.edu.cn, Hu, Mengning, and Chen, Xianfeng. Sat . "An improved three-dimensional two-temperature model for multi-pulse femtosecond laser ablation of aluminum". United States. doi:10.1063/1.4907990.
@article{osti_22413080,
title = {An improved three-dimensional two-temperature model for multi-pulse femtosecond laser ablation of aluminum},
author = {Zhang, Jinping and Chen, Yuping, E-mail: ypchen@sjtu.edu.cn and Hu, Mengning and Chen, Xianfeng},
abstractNote = {In this paper, an improved three-dimensional two-temperature model for multi-pulse femtosecond laser ablation of aluminum was proposed and proved in our experiment. Aiming to achieve hole-drilling with a high ratio of depth/entrance diameter in vacuum, this model can predict the depth and radius of the drilled holes precisely when employing different laser parameters. Additionally, for multi-pulse laser ablation, we found that the laser fluence and number of pulses are the dominant parameters and the multi-pulse ablation threshold is much lower than the single-pulse one, which will help to obtain high-quality holes.},
doi = {10.1063/1.4907990},
journal = {Journal of Applied Physics},
number = 6,
volume = 117,
place = {United States},
year = {Sat Feb 14 00:00:00 EST 2015},
month = {Sat Feb 14 00:00:00 EST 2015}
}
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  • We demonstrate measurement of uranium isotopes in femtosecond laser ablation plumes using two-dimensional fluorescence spectroscopy (2DFS). The high-resolution, tunable CW-laser spectroscopy technique clearly distinguishes atomic absorption from 235U and 238U in natural and highly enriched uranium metal samples. We present analysis of spectral resolution and analytical performance of 2DFS as a function of ambient pressure. Simultaneous measurement using time-resolved absorption spectroscopy provides information on temporal dynamics of the laser ablation plume and saturation behavior of fluorescence signals. The rapid, non-contact measurement is promising for in-field, standoff measurements of uranium enrichment for nuclear safety and security applications.
  • Here, we demonstrate measurement of uranium isotopes in femtosecond laser ablation plumes using two-dimensional fluorescence spectroscopy (2DFS). The high-resolution, tunable CW-laser spectroscopy technique clearly distinguishes atomic absorption from 235U and 238U in natural and highly enriched uranium metal samples. We present analysis of spectral resolution and analytical performance of 2DFS as a function of ambient pressure. Simultaneous measurement using time-resolved absorption spectroscopy provides information on temporal dynamics of the laser ablation plume and saturation behavior of fluorescence signals. The rapid, non-contact measurement is promising for in-field, standoff measurements of uranium enrichment for nuclear safety and security.
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