Laser-Induced Breakdown Spectroscopy (LIBS) Analysis of Laser Processing in Active Crystal with Nanosecond Laser Pulses

2014 ◽  
Vol 68 (4) ◽  
pp. 475-482 ◽  
Author(s):  
F.C. Alvira ◽  
A. Ródenas ◽  
G.A. Torchia
2003 ◽  
Vol 42 (30) ◽  
pp. 6099 ◽  
Author(s):  
Jon Scaffidi ◽  
Jack Pender ◽  
William Pearman ◽  
Scott R. Goode ◽  
Bill W. Colston ◽  
...  

Author(s):  
David J. Hwang ◽  
Hojeong Jeon ◽  
Costas P. Grigoropoulos

In this study, detailed characteristics of the optical near-field based ablation-induced plasma are investigated. A Cr thin metal film samples are ablated using visible and near infrared nanosecond laser pulses coupled through an optical near-field fiber probe. The ablated plasma evolution is visualized through time-resolved emission imaging and further analyzed via spectral measurement. Unveiled qualitative differences in optical near-field ablation configuration are discussed in comparison with optical far-field ablation. The measured results support implementation of laser-induced breakdown spectroscopy based on optical near-field ablation.


2020 ◽  
Vol 92 (2) ◽  
pp. 20701
Author(s):  
Bo Li ◽  
Xiaofeng Li ◽  
Zhifeng Zhu ◽  
Qiang Gao

Laser-induced breakdown spectroscopy (LIBS) is a powerful technique for quantitative diagnostics of gases. The spatial resolution of LIBS, however, is limited by the volume of plasma. Here femtosecond-nanosecond dual-pulsed LIBS was demonstrated. Using this method, the breakdown threshold was reduced by 80%, and decay of continuous radiation was shortened. In addition, the volume of the plasma was shrunk by 85% and hence, the spatial resolution of LIBS was significantly improved.


2021 ◽  
pp. 000370282110123
Author(s):  
Hemalaxmi Rajavelu ◽  
Nilesh J Vasa ◽  
Satyanarayanan Seshadri

A benchtop Laser-Induced Breakdown Spectroscopy (LIBS) is demonstrated to determine the elemental carbon content present in raw coal used for combustion in power plants. The spectral intensities of molecular CN and C2 emission are measured together with the atomic carbon (C) and other inorganic elements (Si, Fe, Mg, Al, Ca, Na, and K) in the LIBS spectrum of coal. The emission persistence time of C2 molecule emission is measured from the coal plasma generated by a nanosecond laser ablation with a wavelength of 266 nm in the Ar atmosphere. The emission persistence time of molecular C2 emission along with the spectral intensities of major ash elements (Fe, Si, Al, and Ca) and carbon emissions (atomic C, molecular CN, and C2) shows a better relationship with the carbon wt% of different coal samples. The calibration model to measure elemental carbon (wt%) is developed by combining the spectral characteristics (Spectral intensity) and the temporal characteristics (Emission persistence time of C2 molecule emission). The temporal characteristic studies combined with the spectroscopic data in the PLSR (Partial Least Square Regression) model has resulted in an improvement in the root mean square error of validation (RMSEV), and the relative standard deviation (RSD) is reduced from 10.86% to 4.12% and from 11.32% to 6.04%, respectively.


2015 ◽  
Vol 17 (2) ◽  
pp. 147-152 ◽  
Author(s):  
Jie Shen ◽  
Zhengcai Yang ◽  
Xiaoliang Liu ◽  
Yanchao Shi ◽  
Peixi Zhao ◽  
...  

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