This textbook explains the fundamental processes involved in the interaction of electromagnetic radiation with matter. It leads students from a general discussion of electrodynamics, forming the mathematical foundation for the Maxwell equations, to key results such as the Fresnel equations, Snell’s law, and the Brewster angle, deriving along the way the equations for accelerated charges and discussing dipole radiation, Bremsstrahlung and synchrotron radiation. By considering more and more interacting particles, the book advances its treatment of the subject, approaching the solid-state regime using both classical and quantum mechanical approaches to describe interaction paths with electromagnetic radiation. Finally, specific interactions of laser radiation with matter are explained such as ultrafast, coherent, and selective interaction. With an emphasis on achieving an intuitive grasp of the basic physics underlying common laser technology, this textbook is ideal for graduate students seeking both a better fundamental and applied understanding of laser–matter interaction.
Author(s): Alexander Horn
Publisher: Springer
Year: 2022
Language: English
Pages: 443
City: Cham
Preface
Contents
Acronyms
Part I Electromagnetic Radiation
1 Properties of Electromagnetic Radiation
1.1 Fundamental Interactions
1.1.1 Nuclear Forces
1.1.2 Electromagnetic Force
1.1.3 Gravitational Force
1.2 Wave and Particle Description of Electromagnetic Radiation
1.3 Photon Description
1.4 Maxwell Equations
1.4.1 Maxwell Equations in Vacuum
1.4.2 Continuity Equation
1.4.3 Integral Description of Maxwell Equations
1.5 Electromagnetic Waves
1.5.1 Derivation of Wave Equations
1.5.2 Fundamentals on Waves
1.5.3 Orthogonality of the Vector Fields
1.5.4 Scalar and Vector Potential
1.6 Energy Density of Electromagnetic Wave
1.6.1 Electrostatic Approach
1.6.2 Generalization to Electromagnetic Fields
1.6.3 Planar Electromagnetic Waves
1.6.4 Phase and Group Velocity
1.7 Laser Radiation
1.7.1 Spatial and Temporal Properties
1.7.2 Coherence
1.7.3 Spectral Modulation
References
2 Generation of Electromagnetic Radiation
2.1 Discrete and Continuous Transitions
2.2 Spontaneous Emission
2.3 Acceleration of a Free Charge
2.3.1 General Aspects on the Retardation
2.3.2 General Solution of a Retarded Wave Equation
2.3.3 Maxwell Equations for a Moving Charge
2.4 Emission of Accelerated Charges
2.4.1 Collinear Velocity and Acceleration Vectors
2.4.2 Acceleration Perpendicular to the Velocity
2.4.3 Periodic Oscillation of a Charged Particle
2.5 Black-Body Radiation
2.5.1 One-Dimensional Hollow Black Body
2.5.2 Three-Dimensional Hollow Black Body
2.5.3 High- and Low Photon Energy Limits
2.5.4 The Stefan–Boltzmann Law
2.5.5 Wien's Displacement Law
2.5.6 Emitted Radiation Power
2.5.7 Real Thermal Emitter
2.6 Laser-Generated X-Rays
2.7 Concluding Remarks
References
Part II Interaction of Particles with Electromagnetic Radiation
3 Elastic Scattering at Charged Particles
3.1 Free Electron
3.1.1 Radiation Force
3.1.2 External Field
3.1.3 Dipole Moment and Differential Power per Solid Angle
3.2 Bounded Electron
3.2.1 Equation of Motion of a Weakly-Bounded Electron
3.2.2 Radiation Force
3.2.3 External Field
3.2.4 Dipole Moment and Differential Power per Solid Angle
3.3 Cross-Section
3.4 Polarization of Scattered Radiation
3.5 Photo-Excitation of Atoms
3.5.1 Linear Scattering
3.5.2 Non-linear Scattering
4 Inelastic Scattering and Absorption
4.1 Free Carrier Absorption—Inverse Bremsstrahlung
4.2 Raman Scattering
4.3 Photo-Ionization or Photo-Effect
4.4 Ponderomotive Energy and Force
4.5 Non-linear Photo-Ionization
4.5.1 Tunnel Ionization
4.5.2 Multi-photon Ionization
4.5.3 Keldysh Parameter for Atoms
4.5.4 Above-Threshold Multi-photon Ionization
4.6 Compton Scattering
4.7 Pair Production
References
5 Scattering by Many Charges
5.1 Attenuation Coefficient
5.2 Coherent Scattering
References
Part III Interaction with Condensed Matter Without Absorption
6 Scattering in Matter
6.1 Reversible and Irreversible Interaction
6.2 Maxwell Equations in Matter
6.3 Lorentz Model
6.4 Refractive Index
6.5 Many Different Scatterers
6.6 Wave Equation in Matter
6.7 Straight Propagation in Condensed Matter
6.8 Speed of Light in Media
References
7 Linear Optics
7.1 Steadiness of Fields
7.2 S-Polarized Radiation
7.3 P-Polarized Radiation
7.4 Boundary Conditions with Complex Refractive Index
7.5 Fresnel Equations for Transparent Dielectrics
7.6 Reflectance and Transmittance
7.7 Nearly Perpendicular Irradiation
7.8 Brewster Angle
7.9 Critical Angle for Total Reflection
7.10 Internal Reflection and Evanescent Waves
8 Non-linear Optics
8.1 Principal Equations of Non-linear Optics
8.2 Non-linear Repulsive Forces
8.3 Second-Order Processes
8.3.1 Equation of Motion with Non-centrosymmetric Media
8.3.2 Non-linear Polarization Density
8.3.3 Differential Equation for the Second Harmonic Field
8.3.4 Second Harmonic Generation
8.3.5 Three-Wave Mixing
8.3.6 Parametric Amplification
8.4 Third-Order Processes
8.4.1 Equation of Motion with Centrosymmetric Media
8.4.2 Four-Wave Mixing
8.4.3 Third-Harmonic Generation
8.4.4 Kerr Effect
8.4.5 Self-focusing
8.4.6 Catastrophic Self-focusing
8.4.7 Self-phase Modulation
References
Part IV Interaction with Absorption
9 Electron Gas in Condensed Matter
9.1 Periodic Potentials
9.2 Electronic Properties at Zero Temperature
9.2.1 Quantized Wave Number and Energy
9.2.2 Density of States
9.2.3 Fermi–Dirac Distribution at T=0 K
9.3 Electronic Properties at Higher Temperatures
9.3.1 Fermi–Dirac Distribution at Higher Temperatures
9.3.2 High Electron Density: Metals
9.3.3 Low Electron Density: Semiconductors
References
10 Optical Properties of an Electron Gas
10.1 General Aspects—Lambert–Beer's Law
10.2 Electron Gas
10.2.1 Free Electron Gas
10.2.2 Quasi-free Electron Gas
11 Band Theory of Crystals
11.1 Electronic Band Formation
11.2 Valence and Conduction Bands
11.2.1 Crystals at Absolute Zero Temperature
11.2.2 Crystals at Higher Temperatures
11.2.3 Electrons and Holes in Semiconductors
11.2.4 Electrons in the Conduction Band of Metals
11.3 Band Structure and Dispersion Relation in Crystals
11.4 Non-crystalline Matter
References
12 Linear Absorption
12.1 Absorption in Condensed Matter
12.2 Interband Excitation
12.2.1 Reduced Band Structure Plot
12.2.2 Dielectrics and Semiconductors
12.2.3 Transition Metals
12.3 Intraband Excitation
12.4 Non-crystalline Matter—Disordered Matter
12.5 Excited State Transitions
12.5.1 Dielectrics and Semiconductors
12.5.2 Recombination and Meta-Stable States
12.5.3 Excited Transition Metals
12.6 Optical Properties of Metals
12.6.1 Non-excited Metals
12.6.2 Excited Dielectrics
References
13 Non-linear Absorption
13.1 Excitation Pathways
13.2 Electron Rate Equation
13.3 Non-linear Photo-Excitation
13.3.1 Keldysh Parameter for Crystals
13.3.2 Tunnel Excitation
13.3.3 Multi-photon Excitation
13.3.4 Non-linear Photo-Excitation
13.3.5 Two-Photon Absorption
13.3.6 Three-Photon Absorption
13.4 Impact Ionization
13.5 Channeling and Filamentation
13.5.1 Channeling
13.5.2 Filamentation
References
14 Heating
14.1 Process Steps of Heating
14.2 Two-Temperature Model
14.3 Derivation of the Heat Equation
14.4 Heating of Metals
14.5 Thermophysical Properties of the Electron System
14.5.1 Heat Capacity of the Electron System
14.5.2 Thermal Conductivity of the Electron System
14.5.3 Electron-Phonon Coupling Parameter
14.6 Thermodynamic Properties of the Phonon System
14.6.1 Heat Capacity of the Phonon System
14.6.2 Thermal Conductivity of the Phonon System
14.7 Numerical Approach
14.8 Examples for Laser-Heated Metals
14.8.1 Nanosecond Laser Radiation
14.8.2 Femtosecond Laser Radiation
References
15 Phase Transitions
15.1 Laser-Induced Phase Changes
15.1.1 Slow Heat Transfer
15.1.2 Fast Heat Transfer
15.2 Heating with Phase Transitions—Modeling
15.3 Thermo-physical Equations
References
Part V Selected Applications in Metrology
16 Reflectometry
16.1 Measurement Methods
16.2 Pump and Probe Metrology
16.3 Time-Resolved Reflectometry
16.3.1 Principle and Set-Up
16.3.2 Examples
References
17 Ellipsometry
17.1 Fundamentals on Polarization States
17.2 Principles of Ellipsometry
17.3 Experimental Approach
17.4 Reflection at One Interface
17.5 Reflection at Many Interfaces for Thin Layers
17.6 Layer- and Dispersion-Models
17.7 Imaging Ellipsometry
17.7.1 Principle Set-Up
17.7.2 Spatial-Resolved Measurement
17.8 Space- and Time-Resolved Ellipsometry
17.8.1 Principle Set-Up
17.8.2 Examples
References
18 Nomarski Microscopy
18.1 Principle of Nomarski Microscopy
18.2 Time-Resolved Nomarski Microscopy
18.3 Examples
Reference
19 White-Light Interferometry
19.1 Principle of Mach-Zehnder Interferometry
19.2 White-Light Interferometry
19.3 Pump-Probe White-Light Interferometry
19.4 Super-Continuum Source
19.5 Interferogram Analysis
19.6 Examples
19.7 Conclusion
Reference
Appendix Bibliography
Index
