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Laser-induced breakdown spectroscopy (LIBS) is an emerging technique for determining ... 978-0-521-85274-6 - Laser-Induced Breakdown Spectroscopy ( LIBS): Fundamentals and Applications. Edited by Andrzej W. Miziolek, Vincenzo Palleschi and Israel Schechter ... o A. Miziolek, V. Palleschi and I. Schechter 2006.

Cambridge University Press 978-0-521-85274-6 - Laser-Induced Breakdown Spectroscopy (LIBS): Fundamentals and Applications Edited by Andrzej W. Miziolek, Vincenzo Palleschi and Israel Schechter Frontmatter More information

L A S E R - I N D U C E D B R E A K D OW N S P E C T RO S C O P Y ( L I B S ) Laser-induced breakdown spectroscopy (LIBS) is an emerging technique for determining elemental composition in real-time. With the ability to analyze and identify chemical and biological materials in solids, liquids, and gaseous forms with little or no sample preparation, it is more versatile than conventional methods and is ideal for on-site analysis. This is the first comprehensive reference book explaining the fundamentals of the LIBS phenomenon, its history, and its fascinating applications across 18 chapters written by recognized leaders in the field. Over 300 illustrations aid understanding. This book will be of significant interest to researchers in chemical and materials analysis within academia, government, military, and industry. Andrzej W. Miziolek is a Senior Research Physicist at the US Army Research Laboratory. His work is currently concentrated on nanomaterials research and on the development of the LIBS sensor technology. Vincenzo Palleschi is a researcher in the Institute for Chemical-Physical Processes at the Italian National Research Council and, in particular, the Applied Laser Spectroscopy Laboratory. Israel Schechter is Professor of Chemistry in the Department of Chemistry at the Technion–Israel Institute of Technology. His main scientific interest is in new methods for fast analysis of particulate materials.

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L A S E R - I N D U C E D B R E A K D OW N S P E C T RO S C O P Y ( L I B S ) Fundamentals and Applications Edited by A N D R Z E J W. M I Z I O L E K US Army Research Laboratory

V I N C E N Z O PAL L E S C H I Instituto per i Processi Chimico-Fisici, Italy

ISRAEL SCHECHTER Technion–Israel Institute of Technology, Haifa, Israel

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cambridge university press Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, S˜ao Paulo Cambridge University Press The Edinburgh Building, Cambridge CB2 2RU, UK Published in the United States of America by Cambridge University Press, New York www.cambridge.org Information on this title: www.cambridge.org/9780521852746  C A. Miziolek, V. Palleschi and I. Schechter 2006

A. Miziolek’s contributions are a work of the United States Government and are not protected by copyright in the United States. This publication is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. First published 2006 Printed in the United Kingdom at the University Press, Cambridge A catalog record for this publication is available from the British Library ISBN-13 978-0-521-85274-6 hardback ISBN-10 0-521-85274-9 hardback

Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate.

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Contents

List of contributors page x Preface xv 1 History and fundamentals of LIBS 1 David A. Cremers and Leon J. Radziemski 1.1 Introduction 1 1.2 Basic principles 1 1.3 Characteristics of LIBS 5 1.4 LIBS as an analytical technique 17 1.5 Early LIBS instruments 27 1.6 Components for a LIBS apparatus 30 1.7 Conclusion 36 1.8 References 36 2 Plasma morphology 40 Israel Schechter and Valery Bulatov 2.1 Introduction 40 2.2 Experimental imaging techniques 41 2.3 Time-integrated morphology 59 2.4 Time-resolved morphology: excitation by medium laser pulses (1–100 ns) 73 2.5 Time-resolved morphology: excitation by long laser pulses (>100 ns) 110 2.6 Time-resolved morphology: excitation by short laser pulses (fs–ps) 112 2.7 Time-resolved morphology: excitation by double laser pulses 113 2.8 Conclusions 118 2.9 References 118 3 From sample to signal in laser-induced breakdown spectroscopy: a complex route to quantitative analysis 122 E. Tognoni, V. Palleschi, M. Corsi, G. Cristoforetti, N. Omenetto, I. Gornushkin, B. W. Smith and J. D. Winefordner 3.1 Introduction 122 3.2 The characteristics of laser-induced plasmas and their influence on quantitative LIBS analysis 123 v

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3.3 Quantitative analysis 3.4 Conclusions 3.5 Appendix. Table of representative limits of detection 3.6 References Laser-induced breakdown in gases: experiments and simulation Christian G. Parigger 4.1 Introduction 4.2 Laser-induced ignition application 4.3 Focal volume irradiance distribution 4.4 Hydrogen Balmer series atomic spectra 4.5 Diatomic molecular emission spectra 4.6 Simulation by use of the program NEQAIR 4.7 Computational fluid dynamic simulations 4.8 Summary 4.9 References Analysis of aerosols by LIBS Ulrich Panne and David Hahn 5.1 Introduction to aerosol science 5.2 Laser-induced breakdown of gases 5.3 Analysis of aerosols by LIBS 5.4 Applications of aerosol analysis by LIBS 5.5 Future directions 5.6 References Chemical imaging of surfaces using LIBS J. M. Vadillo and J. J. Laserna 6.1 Introduction 6.2 LIBS chemical imaging: operational modes 6.3 Spatial resolution in LIBS imaging 6.4 Applications of LIBS imaging 6.5 Concluding remarks and outlook 6.6 References Biomedical applications of LIBS Helmut H. Telle and Ota Samek 7.1 Introduction 7.2 Investigation of calcified tissue materials 7.3 Investigation of “soft” tissue materials with cell structure 7.4 Investigation of bio-fluids 7.5 Investigation of microscopic bio-samples 7.6 Concluding remarks 7.7 References

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Cambridge University Press 978-0-521-85274-6 - Laser-Induced Breakdown Spectroscopy (LIBS): Fundamentals and Applications Edited by Andrzej W. Miziolek, Vincenzo Palleschi and Israel Schechter Frontmatter More information

Contents

8 LIBS for the analysis of pharmaceutical materials Simon B´echard and Yves Mouget 8.1 Introduction 8.2 Needs of the pharmaceutical industry 8.3 Comparison of LIBS with the current technologies 8.4 Components of a LIBS instrument for applications in the pharmaceutical industry 8.5 Applications of LIBS to the analysis of pharmaceutical materials 8.6 Conclusions 8.7 References 9 Cultural heritage applications of LIBS Demetrios Anglos and John C. Miller 9.1 Introduction 9.2 Art and analytical chemistry 9.3 Why LIBS in cultural heritage? 9.4 Physical principles 9.5 Instrumentation 9.6 Analytical parameters and methodology 9.7 Examples of LIBS analysis in art and archaeology 9.8 LIBS in combinations with other techniques 9.9 Concluding remarks 9.10 References 10 Civilian and military environmental contamination studies using LIBS J. P. Singh, F. Y. Yueh, V. N. Rai, R. Harmon, S. Beaton, P. French, F. C. DeLucia, Jr., B. Peterson, K. L. McNesby and A. W. Miziolek 10.1 Introduction 10.2 Applications of the ADA portable LIBS unit 10.3 Applications of DIAL’s portable LIBS system 10.4 Conclusion 10.5 References 11 Industrial applications of LIBS Reinhard Noll, Volker Sturm, Michael Stepputat, Andrew Whitehouse, James Young and Philip Evans 11.1 Introduction 11.2 Metals and alloys processing 11.3 Scrap material sorting and recycling 11.4 Nuclear power generation and spent fuel reprocessing 11.5 Miscellaneous industrial applications of LIBS 11.6 References

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12 Resonance-enhanced LIBS N. H. Cheung 12.1 Introduction to resonance-enhanced LIBS 12.2 Basic principles of spectrochemical excitation in laser-induced plasmas 12.3 RELIPS analysis of solids 12.4 Liquid samples 12.5 Gaseous samples 12.6 Conclusion: resonance-enhanced LIBS as an analytical tool 12.7 References 13 Short-pulse LIBS: fundamentals and applications R. E. Russo 13.1 Introduction 13.2 Effect of pulse duration on ablation 13.3 Effect of pulse duration on plasma 13.4 Picosecond-induced electron plasma 13.5 Femtosecond plasma 13.6 Short-pulse LIBS 13.7 Conclusion 13.8 References 14 High-speed, high-resolution LIBS using diode-pumped solid-state lasers Holger Bette and Reinhard Noll 14.1 Introduction 14.2 Diode-pumped solid-state lasers 14.3 State of the art 14.4 Scanning LIBS 14.5 Laser-induced crater geometry and spatial resolution of high-speed, high-resolution scanning LIBS with DPSSL 14.6 References 15 Laser-induced breakdown spectroscopy using sequential laser pulses Jack Pender, Bill Pearman, Jon Scaffidi, Scott R. Goode and S. Michael Angel 15.1 Introduction 15.2 Dual-pulse LIBS 15.3 Summary 15.4 References 16 Micro LIBS technique Pascal Fichet, Jean-Luc Lacour, Denis Menut, Patrick Mauchien, Annie Rivoallan, C´ecile Fabre, Jean Dubessy and Marie-Christine Boiron 16.1 Introduction 16.2 Experimental set-up for the micro LIBS system 16.3 Results and discussion

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Cambridge University Press 978-0-521-85274-6 - Laser-Induced Breakdown Spectroscopy (LIBS): Fundamentals and Applications Edited by Andrzej W. Miziolek, Vincenzo Palleschi and Israel Schechter Frontmatter More information

Contents

16.4 Conclusion 16.5 References 17 New spectral detectors for LIBS Mohamad Sabsabi and Vincent Detalle 17.1 Chapter organization 17.2 Introduction 17.3 Multidetection in LIBS 17.4 Evaluation of an echelle spectrometer/ICCD for LIBS applications 17.5 Advantages and limitations 17.6 Choice of an optical setup for LIBS 17.7 Conclusions 17.8 References 18 Spark-induced breakdown spectroscopy: a description of an electrically generated LIBS-like process for elemental analysis of airborne particulates and solid samples Amy J. R. Hunter and Lawrence G. Piper 18.1 Introduction 18.2 Basic description of SIBS processes and hardware 18.3 Application-specific considerations 18.4 Applications and results 18.5 Discussion and future directions 18.6 References Index

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Contributors

Marie-Christine Boiron Equipes Interactions entre Fluides et Min´eraux, UMR 7566 G2R - CREGU G´eologie et Gestion des Ressources Min´erales et Energ´etiques, Universit´e Henri Poincar´e, BP-239, 54506-Vandoeuvre-les Nancy Cedex, France

S. Michael Angel Department of Chemistry and Biochemistry, The University of South Carolina, Columbia, SC 29208, USA Demetrios Anglos Institute of Electronic Structure and Laser, Foundation for Research and Technology – Hellas, PO Box 1527, GR 71110, Heraklion, Crete, Greece

Valery Bulatov Department of Chemistry, Technion–Israel Institute of Technology, Haifa 32000, Israel

S. Beaton ADA Technologies, Inc., Littleton, CO, USA

N. H. Cheung Department of Physics, Hong Kong Baptist University, Kowloon Tong, Hong Kong, People’s Republic of China

Simon B´echard Pharma Laser Inc., 75 Blvd. de Mortagne, Boucherville, Qu´ebec, Canada J4B 6Y4

M. Corsi Instituto per i Processi Chemico-Fisici del CNR, Area della Ricerca di Pisa, Via G. Moruzzi 1, 56124 Pisa, Italy

Holger Bette Lehrstuhl f¨ur Lasertechnik (LLT), RWTH Aachen, Steinbachstr. 15, 52074 Aachen, Germany

David A. Cremers Chemistry Division, x

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List of contributors

Los Alamos National Laboratory, Los Alamos, NM, USA G. Cristoforetti Instituto per i Processi Chemico-Fisici del CNR, Area della Ricerca di Pisa, Via G. Moruzzi 1, 56124 Pisa, Italy F. C. DeLucia, Jr. US Army Research Laboratory, AMSRL-WM-BD, Aberdeen Proving Ground, MD 21005–5069, USA Vincent Detalle Industrial Materials Institute, National Research Council of Canada, 75 Blvd. de Mortagne, Boucherville, Qu´ebec, Canada J4B 6Y4 Jean Dubessy Equipes Interactions entre Fluides et Min´eraux, UMR 7566 G2R - CREGU G´eologie et Gestion des Ressources Min´erales et Energ´etiques, Universit´e Henri Poincar´e, BP-239, 54506-Vandoeuvre-les Nancy Cedex, France Philip Evans Applied Photonics Ltd, Unit 8 Carleton Business Park, Carleton New Road, Skipton, North Yorkshire BD23 2DE, UK

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C´ecile Fabre Equipes Interactions entre Fluides et Min´eraux, UMR 7566 G2R - CREGU G´eologie et Gestion des Ressources Min´erales et Energ´etiques, Universit´e Henri Poincar´e, BP-239, 54506-Vandoeuvre-les Nancy Cedex, France Pascal Fichet CEA Saclay, DPC/SCPA/LALES, 91191 Gif Sur Yvette, France P. French ADA Technologies, Inc., Littleton, CO, USA Scott R. Goode Department of Chemistry and Biochemistry, The University of South Carolina, Columbia, SC 29208, USA I. Gornushkin Department of Chemistry, University of Florida, Gainesville, FL 32611, USA David Hahn Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611–6300, USA R. Harmon US Army Research Laboratory, Army Research Office, PO Box 12211,

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Research Triangle Park, NC, USA Amy J. R. Hunter Physical Sciences Inc., 20 New England Business Center, Andover, MA 01810, USA Jean-Luc Lacour CEA Saclay, DPC/SCPA/LALES, 91191 Gif Sur Yvette, France J. J. Laserna Department of Analytical Chemistry, University of M´alaga, M´alaga, Spain K. L. McNesby US Army Research Laboratory, AMSRL-WM-BD, Aberdeen Proving Ground, MD 21005–5069, USA Patrick Mauchien CEA Saclay, DPC/SCPA/LALES, 91191 Gif Sur Yvette, France Denis Menut CEA Saclay, DPC/SCPA/LALES, 91191 Gif Sur Yvette, France John C. Miller Life Sciences Division, Oak Ridge National Laboratory, PO Box 2008,

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List of contributors

Oak Ridge, TN 37830–6125, USA Present address: Chemical Sciences, Geosciences and Biosciences Division, Basic Energy Sciences, Office of Science SC–14 Germantown Building, US Department of Energy, 1000 Independence Avenue, SW Washington, DC 20585–1290, USA A. W. Miziolek US Army Research Laboratory, AMSRL-WM-BD, Aberdeen Proving Ground, MD 21005–5069, USA Yves Mouget Pharma Laser Inc., 75 Blvd. de Mortagne, Boucherville, Qu´ebec, Canada J4B 6Y4 Reinhard Noll Fraunhofer-Institut f¨ur Lasertechnik (ILT), Steinbachstr. 15, 52074 Aachen, Germany N. Omenetto Department of Chemistry, University of Florida, Gainesville, FL 32611, USA V. Palleschi Instituto per i Processi Chemico-Fisici del CNR, Area della Ricerca di Pisa, Via G. Moruzzi 1, 56124 Pisa, Italy

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List of contributors

Ulrich Panne Laboratory for Applied Laser Spectroscopy, Institute of Hydrochemistry, Technical University Munich, Marchioinistrasse 17, D-81377 Munich, Germany Christian G. Parigger The University of Tennessee Space Institute, Center for Laser Applications, 411 B. H. Goethert Parkway, Tullahoma, TN 37388, USA Bill Pearman Department of Chemistry and Biochemistry, The University of South Carolina, Columbia, SC 29208, USA Jack Pender Department of Chemistry and Biochemistry, The University of South Carolina, Columbia, SC 29208, USA B. Peterson US Army Research Laboratory, AMSRL-WM-BD, Aberdeen Proving Ground, MD 21005–5069, USA Lawrence G. Piper Physical Sciences Inc., 20 New England Business Center, Andover, MA 01810, USA

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Leon J. Radziemski Physics Department, Washington State University, Pullman, WA, USA V. N. Rai Diagnostics Instruments and Analysis Laboratory (DIAL), Mississippi State University, 205 Research Blvd., Starkville, MS 39759–7704, USA Annie Rivoallan CEA Saclay, DPC/SCPA/LALES, 91191 Gif Sur Yvette, France R. E. Russo Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA Mohamad Sabsabi Industrial Materials Institute, National Research Council of Canada, 75 Blvd. de Mortagne, Boucherville, Qu´ebec, Canada J4B 6YA Ota Samek Department of Physical Engineering, Technical University of Brno, Technicka 2, 61669 Brno, Czech Republic Jon Scaffidi Department of Chemistry and Biochemistry, The University of South Carolina, Columbia, SC 29208, USA

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List of contributors

Israel Schechter Department of Chemistry, Technion–Israel Institute of Technology, Haifa 32000, Israel

Area della Ricerca di Pisa, Via G. Moruzzi 1, 56124 Pisa, Italy

J. P. Singh Diagnostics Instruments and Analysis Laboratory (DIAL), Mississippi State University, 205 Research Blvd., Starkville, MS 39759–7704, USA

J. M. Vadillo Department of Analytical Chemistry, University of M´alaga, M´alaga, Spain

B. W. Smith Department of Chemistry, University of Florida, Gainesville, FL 32611, USA

Andrew Whitehouse Applied Photonics Ltd, Unit 8 Carleton Business Park, Carleton New Road, Skipton, North Yorkshire BD23 2DE, UK

Michael Stepputat Fraunhofer-Institut f¨ur Lasertechnik (ILT), Steinbachstr. 15, 52074 Aachen, Germany

J. D. Winefordner Department of Chemistry, University of Florida, Gainesville, FL 32611, USA

Volker Sturm Fraunhofer-Institut f¨ur Lasertechnik (ILT), Steinbachstr. 15, 52074 Aachen, Germany

James Young Applied Photonics Ltd, Unit 8 Carleton Business Park, Carleton New Road, Skipton, North Yorkshire BD23 2DE, UK

Helmut H. Telle Department of Physics, University of Wales Swansea, Singleton Park, Swansea SA2 8PP, UK Elisabetta Tognoni Instituto per i Processi Chemico-Fisici del CNR,

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F. Y. Yueh Diagnostics Instruments and Analysis Laboratory (DIAL), Mississippi State University, 205 Research Blvd., Starkville, MS 39759–7704, USA

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Preface

Richard E. Russo and Andrzej W. Miziolek LIBS (laser-induced breakdown spectroscopy) has been described as “a future super star” in a 2004 review article by Dr. James Winefordner, a world-renowned analytical spectroscopist.1 LIBS is the only technology that can provide distinct spectral signatures characteristic of all chemical species in all environments. LIBS can be used to chemically characterize any sample: rocks, glasses, metals, sand, teeth, bones, weapons, powders, hazards, liquids, plants, biological material, polymers, etc. LIBS can be performed at atmospheric pressure, in a vacuum, at the depths of the ocean, or extraterrestrially. LIBS can respond in less than a second, indicating if a spilled white power is innocuous or hazardous, using a single laser shot. A unique attribute of LIBS is that samples do not need to fluoresce, or be Raman or infrared (IR) active. It is the simplicity of LIBS that allows this diversity of applications; simply strike any sample with a pulsed laser beam and measure a distinct optical spectrum. The laser beam initiates a tiny luminous plasma from ablated sample mass. The plasma spectrum is a signature of the chemical species in the sample; spectral data analysis provides the chemical species composition and relative abundance. Because a pulsed laser beam initiates the LIBS plasma, there is no physical contact with the sample; laboratory and open-path standoff applications are readily employed. Simply put, the LIBS phenomenon represents an efficient engine to convert the chemical information of the target material to light information that can be captured efficiently and analyzed thoroughly by modern spectroscopic instrumentation and data analysis/chemometrics software. LIBS has been aggressively investigated for environmental, industrial, geological, planetary, art, and medical applications since the early 1980s, although initial LIBS papers appeared with the discovery of the ruby laser in 1962.1 A comprehensive source of literature describing LIBS research and applications can be found in Applied Optics,2 which dedicated a special issue to this technology, as well as an extensive review in 2004.3 Although traditionally classified as an elemental analysis technology, the use of broadband high-resolution 1

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J. D. Winefordner, I. B. Gornushkin, T. Correll, E. Gibb, B. W. Smith, and N. Omenetto, Comparing several atomic spectrometric methods to the super stars: special issue on laser induced breakdown spectrometry, LIBS, a future super star. J. Anal. Atom. Spectrom., 19 (2004), 106–108. See Appl. Opt., 42 (30) (2003). W. B. Lee, J. Wu, Y.-III Lee and J. Sneddon, Recent applications of laser-induced breakdown spectrometry: a review of material approaches, Appl. Spectros. Rev., 39 (2004), 27–97.

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spectrometers has recently extended LIBS applications to molecular species identification. The ability to detect molecular and elemental signatures with a single laser pulse offers unprecedented performance for emerging medical, biological, environmental, and security applications. With the growth and evolution of LIBS phenomenon understanding and application areas there has been a corresponding increase in LIBS practitioners, both engineers and scientists, as well as a growth in LIBS commercial activities, in both instrument manufacturing and applications for hire. In fact, the world-wide LIBS community has established a tradition of international conferences on a two-year cycle that include LIBS 2000 (Tirrenia, Italy), LIBS 2002 (Orlando, USA), LIBS 2004 (M´alaga, Spain), and LIBS 2006 (Montreal, Canada). The European LIBS community has also established the EMSLIBS (Euro-Mediterranean Symposium) series with EMSLIBS 2001 (Cairo, Egypt), EMSLIBS 2003 (Crete, Greece), and EMSLIBS 2005 (Aachen, Germany). In addition there have been a multitude of LIBS symposia associated with Optical Society of America, Pittcon, and FACSS meetings. This book describes the history, current research in understanding fundamental processes, research to improve measurement performance, and examples of numerous applications requiring parts per million (p.p.m.) and parts per billion (p.p.b.) detection levels. Several chapters describe research efforts dedicated to improving detection capabilities. Achieving sub-p.p.b. levels would allow LIBS to compete with vacuum-based mass spectrometric measurements, without requiring a vacuum. As described throughout this book, there is a tremendous international effort to advance the LIBS technology, by addressing multiple laser pulses, short duration laser pulses, and new instrumentation. One area to increase sensitivity would be to utilize ablated mass more efficiently; current LIBS analysis detects only a fraction of the mass ablated and excited to optical emission. Focused fundamental research on laser-induced plasmas will provide advanced knowledge for efficiently generating, exciting, and detecting mass. There is a large body of supporting literature on laser ablation for other applications (micromachining, materials fabrication, nanotechnology, thin-film deposition) that is germane to LIBS; the fundamental mechanisms are the same, but the optimum parameters for application are not. Optimum parameters need to be established for analyzing diverse samples, for example organic residues compared with inorganic refractory bulk samples. Understanding plasma physics can provide new approaches for increased sensitivity by using external (for example light, radio frequency, magnetic fields) means for producing longer-lived, hotter, and denser plasmas. There have been numerous efforts to study the influence of the laser beam properties (pulse duration, wavelength, energy, and number of pulses) on LIBS analytical performance. The laser beam can deliver energy from femtoseconds to microseconds in duration. On the other hand, the LIBS plasma duration is generally several microseconds, although research needs to establish laser–plasma–property time relationships. Most LIBS applications are based on using a laser with wavelength of 1064 nm. Wavelength contributes to plasma heating with nanosecond pulses, but research needs to establish if IR is best when using short pulsed (femtosecond and picosecond) lasers, and the role of Bremsstrahlung absorption. The use of double and triple pulses is being aggressively

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Preface

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investigated for improving sensitivity and reducing ambient interferences. Currently, the UV–IR (ultraviolet–infrared) spectral region is interrogated for analysis, but other spectral regions, such as hyperspectral, may provide enhanced measurement capabilities. Just as the broadband spectrometer opened new vistas in LIBS applications, understanding measurement principles will advance performance specifications for existing and new LIBS applications. Implementation of LIBS in a suite of applications requires diverse yet similar instrumentation. For example, LIBS can be used with a simple lens to focus the laser beam within a few millimeters from the laser, with an optical fiber to carry the laser beam to a remote physical location, or by using a telescope for open-path standoff applications. Improved LIBS systems for long-distance standoff measurements will benefit from advanced optical configurations. Other spectroscopic technologies (Raman, fluorescence, absorbance, light scattering) perform in open-path configurations, although they do not possess the versatility of LIBS. However, it would be easy to integrate LIBS with Raman and laser-induced fluorescence for additional measurement capabilities. An integrated system could use light scattering to identify a suspect particle based on its morphology and then Q-switch the same laser for simultaneous LIBS – all in the same system. A concern for open-path standoff laser-based analysis is eye safety. Although the FDA in the USA has established limits for pulsed exposure, these limits are for unfocused laser beams; LIBS requires a focused laser beam. As research progresses to advance LIBS sensitivity using various laser wavelengths, low-level eye-safe operation will be viable. New applications of LIBS are expected in medical, biological, security, and nanotechnology. With the international effort to fabricate nano-devices, -structures, and -particles, new technologies will be required to ensure that these systems abide by their design criteria. LIBS can fulfill this requirement, but will need to operate on smaller spatial scales and with enhanced sensitivity. The widespread utilization of LIBS for these applications will require development of comprehensive spectral databases and data manipulation algorithms. Spectral libraries can be established for voluminous chemical species and rapidly be evaluated to determine distinct signature for classes of species. Mass spectroscopy, Raman spectroscopy, fluorescence, IR, NMR (nuclear magnetic resonance), and almost all spectral analytical technologies benefit from the use of spectral libraries – as will LIBS. This book challenges you to benefit from the current expertise and to imagine new applications and ideas for advancing LIBS. The chapters present the current status of fundamental and applied LIBS studies, from a community excited by the numerous capabilities and possibilities. Chemical analysis is a critical component of world survivability – for understanding nature, contamination, health, climate, microelectronics, terrorism, advanced materials, and other things. We believe that LIBS will play a dominant role in every aspect of society for chemical analysis. With continued research and application, LIBS is becoming a future super star of analytical spectroscopy.

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