Instrumental configuration effect on the libs acoustic signal response


              Markéta BOSÁKOVÁ^1,2, Karel NOVOTNÝ^1, Javier MOROS^2, Javier LASERNA^2


^1Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech
Republic

^2 UMALASERLAB, Departamento de Química Analítica, Universidad de Málaga, C/Jiménez Fraud 4, Malaga
29010, Spain

Email of presenting author: 451320@mail.muni.cz


During years, potential of acoustic shockwaves from laser-induced plasmas has been trying to
exploit as a standardization score to the optical emission properties, mainly to correct/normalize
shot-to-shot plasma inherent instabilities. However, nowadays its in-depth study is revealing that
its benefits can go even further, by physically characterizing the studied samples and allowing the
enhancement of the discriminative power between spectrally similar samples via data fusion
strategies.^1,2

As is well known, the instrumentation used for the generation of the plasma and the subsequent
spectroscopic detection of the light it emits, significantly conditions the analytical information
obtained. In this sense, and considering the associative character of the plasma with the acoustic
wave recorded, in this work, research is intended to evaluate how the instrumentation affects the
recorded acoustic signal; Nd:YAG lasers operating at 1064 nm and 266 nm and miscellaneous types of
microphones (commercially available and ad-hoc built, varying in sensitivity, frequency response,
…) have been considered.

In parallel with multielemental LIBS imaging, given the simultaneity of the optical and acoustic
phenomena, surface acoustic mapping from different samples performance was evaluated. Results
revealed that the first peak-to-peak acoustic amplitude in the sound wave recorded finely describes
the morphological characteristics of the interrogated surface; an information that can contribute
to a much more complete characterization of the sample under study.


References

[1] Palanco, S. and LASERNA, J. Spectral analysis of the acoustic emission of laser-produced
plasmas. Applied Optics. 2003, 42(30). ISSN 0003-6935. DOI:10.1364/AO.42.006078

[2] Alvarez-Llamas, C., PUROHIT, P., MOROS, J. and LASERNA, J. LIBS-Acoustic Mid-Level Fusion
Scheme for Mineral Differentiation under Terrestrial and Martian Atmospheric Conditions. Analytical
Chemistry. 94(3), 1840-1849. ISSN 0003-2700. DOI:10.1021/acs.analchem.1c04792


Acknowledgements

This work was supported from Operational Programme Research, Development and Education – „Project
Internal Grant Agency of Masaryk University" (No. CZ.02.2.69/0.0/0.0/19_073/0016943)