Laser ablation : effects and applications

Laser ablation is the process of removing material from a solid (or occasionally liquid) surface by irradiating it with a laser beam. At low laser flux, the material is heated by the absorbed laser energy and evaporates or sublimates. At high laser flux, the material is typically converted to a plasma. Usually, laser ablation refers to removing material with a pulsed laser, but it is possible to ablate material with a continuous wave laser beam if the laser intensity is high enough. This book presents current research in the study of laser ablation from across the globe. Topics discussed herein include double-pulse laser ablation of solid targets in ambient gas; using laser ablation ICP-MS and its potential in sampling archaeological skeletal materials; and numerical modeling of laser-matter interactions. TITLE PAGE......Page 4 CONTENTS......Page 6 PREFACE......Page 8 ABSTRACT......Page 14 1. INTRODUCTION......Page 15 Effects on plasma emission......Page 18 Plasma dynamics......Page 24 Mass removal mechanisms, atomized ablated mass and effects of the matrix target......Page 26 Dependence on ambient gas pressure......Page 30 b) Orthogonal Beams Pre-Ablation Configuration......Page 32 c) Orthogonal Beams Re-Heating Configuration......Page 37 3. NANOSECOND-NANOSECOND PULSES COMBINATION: DISCUSSION ON THE MECHANISMS......Page 39 a) Target Heating Effects......Page 40 Laser supported detonation and laser ablation......Page 42 Laser supported detonation wave and ambient gas pressure......Page 45 Laser absorption in double pulse configuration......Page 46 Mass removal mechanisms in DP schemes......Page 48 4. DOUBLE PULSE WITH SHORT AND ULTRASHORT LASER PULSES: EFFECTS AND MECHANISMS......Page 50 PERSPECTIVES AND FUTURE DEVELOPMENT......Page 52 REFERENCES......Page 53 ABSTRACT......Page 58 INTRODUCTION......Page 59 HUNTER GATHERER MOBILITY IN CIS-BAIKAL......Page 60 KHUZHIR-NUGE XIV CEMETERY......Page 62 TOOTH MINERALIZATION......Page 63 LASER ABLATION OF TEETH......Page 65 MATERIALS AND METHODS......Page 66 RESULTS AND DISCUSSION......Page 69 CONCLUSION......Page 105 REFERENCES......Page 106 ABSTRACT......Page 112 1. INTRODUCTION......Page 113 2.1. Primary Mechanisms of the Material Ejection under Nanosecond Laser Action......Page 117 2.2. Secondary Mechanisms: Plasma Plume Expansion after Nanosecond Laser Pulse......Page 119 2.2.1. Combined LP -DSMC method......Page 121 2.2.2. Results of the combined LP -DSMC calculations......Page 123 3.1.1. Metallic targets......Page 126 3.1.2. Dielectric targets......Page 130 3.2. Secondary Mechanisms: Plasma Plume Expansion after Femtosecond Laser Pulse......Page 134 REFERENCES......Page 135 1. INTRODUCTION......Page 140 2.1. Laser Ablation......Page 142 2.2. Laser Fragmentation......Page 143 3. SI-NCS AND SI-NCS BASED COMPOSITES PRODUCED BY LASER ABLATION IN LIQUID MEDIA......Page 144 4. INDUCED SELF-ASSEMBY & TUNING OF SI-NCS OPTICAL PROPERTIES BY NS LASER FRAGMENTATION IN LIQUID MEDIA......Page 147 5. PHYSICS OF THE NANOSECOND-LASER PROCESSINGS IN LIQUID MEDIA......Page 150 CONCLUSION......Page 151 ACKNOWLEDGMENTS......Page 152 REFERENCES......Page 153 INTRODUCTION......Page 156 MECHANISM OF HO:YAG LASER LITHOTRIPSY......Page 157 FIBERS FOR HO:YAG LASER LITHOTRIPSY......Page 159 SAFETY ASPECT OF HO:YAG LASER LITHOTRIPSY......Page 161 REFERENCES......Page 162 1. INTRODUCTION......Page 166 2. MOLECULAR DYNAMICS SIMULATION......Page 168 4. TWO-TEMPERATURE MODELS......Page 169 5. COMPUTATION OF CRATER GEOMETRY......Page 173 REFERENCES......Page 175 Abstract......Page 176 1. Introduction......Page 177 2.1.Two-temperature Model......Page 178 2.3.1. The space-and time-dependence of electron and lattice temperature of target......Page 180 2.3.2. The numerical solution of electron-phonon relaxation time......Page 181 2.3.4. Effect of fluence of femtosecondl aser on the electron-phonon relaxation time......Page 182 2.3.5. Heat-affected zone per pulseas a function of laser fluence......Page 183 3.1. The Effect of Temperature on Heat Capacity and Thermal Conductivity of the Electrons......Page 184 3.2.Electron Temperature Dependences of the Absorption Coefficient and the Absorptivity......Page 185 3.3. Verification of Absorption Coefficient Analytic Approximation......Page 188 3.4.The Improved Two Temperature Model......Page 189 3.5.1. The Time-dependence of Electron and Lattice Temperature of Target......Page 190 3.5.2. Ablation rate per pulse as a function of laser fluence......Page 191 4.1.1.Physical background......Page 193 4.1.2.The contents of ourmodel......Page 194 4.2.Results and Discussions......Page 195 4.2.1.Determination of the value of a......Page 196 4.2.2. The evolvement of vaporization threshold fluence with laser pulse width......Page 197 References......Page 199 INTRODUCTION......Page 204 General Setup of Laser Ablation in Liquids......Page 205 1. Pulse Duration......Page 206 HISTORICAL REVIEW......Page 208 LASER ABLATION OF AN AG TARGET IN LIQUID ENVIRONMENT......Page 211 LASER ABLATION OF AN AU TARGET IN LIQUID ENVIRONMENT......Page 213 FRAGMENTATION OF NP UNDER LASER EXPOSURE IN LIQUIDS......Page 214 SHAPE-SELECTIVE FRAGMENTATION......Page 215 FORMATION OF THE AU-AG ALLOY UNDER LASER IRRADIATION OF NANOPARTICLES......Page 217 NANOPARTICLES OF CU, BRASS, AND BRONZE......Page 219 INTERNAL SEGREGATION OF BRASS NP......Page 221 SELF-INFLUENCE OF A FEMTOSECOND LASER BEAM......Page 223 Ablation of a Ti Target......Page 224 Ablation of Sn......Page 225 W and Mo NP......Page 226 Modeling of Distribution Function......Page 227 INFLUENCE OF INTENSITY DISTRIBUTION OF THE LASER BEAM ON THE SHAPE OF NANOPARTICLES......Page 228 NANOSTRUCTURING OF SOLIDS UNDER THEIR LASER ABLATION IN LIQUIDS......Page 230 EXCITATION OF HIGH ENERGY LEVELS......Page 233 REFERENCES......Page 235 1. INTRODUCTION......Page 240 2.1. Fundamental Processes in Laser Ablation In Liquid......Page 241 2.2. Synthesis of Nanocrystals Using Laser Ablation in Liquid......Page 247 3.1. PLIIR Apparatus......Page 249 3.2. Thermodynamic and Kinetic Factors of PLIIR......Page 250 4.1. Synthesis of Nanodiamonds by PLIIR......Page 253 4.2. Thermodynamic Nucleation of Diamonds upon PLIIR......Page 257 4.3. Graphite-Diamond Phase Transition upon PLIIR......Page 261 4.4. Structural Transformation of Diamonds upon PLIIR......Page 265 4.5. Stability of Nanodiamonds Synthesized by PLIIR......Page 268 CONCLUSION......Page 271 REFERENCES......Page 272 INDEX......Page 280