Strong Field Laser Physics

Description

OPTICAL SCIENCES Contents Contributors Part 1: High-Intensity Laser Sources High-Energy Pulse Compression Techniques 1 Introduction 2 Hollow Fiber Compression Technique 2.1 Propagation Modes in Hollow Fibers 2.2 Nonlinear Pulse Propagation in Hollow Fibers 2.3 General Considerations on the Compression Technique 3 Experimental Results 3.1 Sub-4-fs Regime 4 Applications and Perspectives 5 Conclusions References Ultrafast Laser Amplifier Systems 1 Introduction 2 Ultrashort-Pulse Laser Oscillators 3 Pulse Stretching and Recompression 4 Amplification 5 Limitations in Intense Laser Systems 5.1 Thermal Effects 5.2 Pulse Duration Limitations 5.3 Temporal Contrast of Intense Pulse 5.4 Focusability of Intense Femtosecond Lasers 6 Conclusion References Optical Parametric Amplification Techniques 1 Introduction 2 The Principles and Analysis of Optical Parametric Amplifiers 2.1 Intensity Solution 2.2 Phase Solution 2.3 OPA Spectral Bandwidth 2.4 Limiting Processes 2.5 Maximum Bandwidth Options 2.6 Energy Capacity 2.7 Beam Quality 2.8 Background Noise for an OPA (‘ASE’) 3 OPCPA Schemes and their Optimisation 3.1 The Amplification of Chirped Pulses 3.2 Tunable 10 fs High-Repetition-Rate OPCPA 3.3 Broadband OPCPA Pre-amplifier 3.4 A High Gain OPCPA for Amplification up to Joule Energies 3.5 A PW Opcpa 3.6 Future Potential for a Multi-PW OPCPA 3.7 Phase-Preserving Chirped Pulse OPA 4 Conclusion 5 Parameter Set References Carrier-Envelope Phase of Ultrashort Pulses 1 Introduction 1.1 Evolution of the Carrier-Envelope Phase 2 Measurement and Control of Carrier-Envelope Phase from Mode-Locked Lasers 2.1 Cross-Correlation 2.2 Frequency Domain Description of Carrier-Envelope Phase Evolution in a Mode-Locked Pulse Train 2.3 Frequency Domain Detection of ${\bDelta} \bvarphi$ 2.4 Generation of an Octave-Spanning Spectrum 2.5 Frequency Domain Stabilization 2.6 Phase Noise and Coherence 2.7 Detection of $\bi f_{\bf{0}}$ Using Quantum Interference 2.8 Phase Stabilization with Octave-Spanning Ti:Sapphire Oscillator 2.9 Phase Noise After Pulse Selection 3 Phase Stabilization of Intense Few-Cycle Pulses 3.1 Phase-Stabilized Ti:Sapphire Amplifier System 3.2 Self-Stabilized $\bivarphi$ from an Optical Parametric Amplifier 3.3 Cavity Buildup 4 The Role of $\bivarphi$ in Strong-Field Interactions, Measurement of $\bivarphi$ 4.1 Optical-Field Ionization of Atoms 4.2 Optical-Field-Induced Photoemission from a Metal Surface 4.3 Generation of High-Order Harmonics and Attosecond Pulses 4.4 Attosecond Pulse Generation and Application 4.5 Carrier-Envelope Phase Measurement with Above Threshold Ionization 5 Summary and Outlook References Free-Electron Lasers - High-Intensity X-Ray Sources 1 Introduction 2 The Motion of a Relativistic Electron Through an Undulator Under the Influence of an Electromagnetic Wave 3 Microbunching 4 Start-Up from the Spontaneous Emission 5 Soft X-Ray SASE FEL Facilities 6 Hard X-Ray SASE Free-Electron Lasers 7 Seeding with Coherent Radiation 8 Outlook References Part 2: Laser-Matter Interaction - Nonrelativistic Numerical Methods in Strong Field Physics 1 Introduction 2 Single Active Electron Approximation 2.1 SAE Potentials 2.1.1 Model Potentials 2.1.2 Pseudopotentials 2.1.3 Modifying the Pseudopotentials 2.2 Choice of Gauge 2.3 SAE Calculations 2.4 Discrete Form of the TDSE 2.5 Time Propagation 2.6 Advanced Topics 2.6.1 Elliptic Polarization 2.6.2 Mixed Gauge Propagation 2.7 Computational Scaling 2.8 Photoelectron Spectra 2.8.1 Sample Results 2.9 Photoemission Spectra 2.10 Approximate Dipole Calculation 2.11 Relation to the Strong Field Approximation 2.12 Restricted Ionization Model 3 Multiple Active Electrons 3.1 The Aligned Electron Model 3.2 Orbital-Dependent Potentials 4 Appendix: Velocity Gauge Time Propagation References Principles of Single Atom Physics: High-Order Harmonic Generation, Above-Threshold Ionization and Non-Sequential Ionization 1 Introduction 2 Experimental Conditions and Methods 2.1 Lasers 2.2 Ionization Experiments 2.3 Photon Detection 3 Typical Experimental Results and Historical Perspective 3.1 High-Order Harmonic Generation 3.2 Above-Threshold Ionization 3.3 Non-sequential Ionization 4 Theoretical Methods 5 Strong Field Approximation 5.1 Derivation of SFA 5.2 Strong Field Approximation for HHG 5.3 Generalized Strong Field Approximation for ATI 5.4 Generalized Strong Field Approximation for Non-sequential Ionization 6 Conclusion References Ionization of Small Molecules by Strong Laser Fields 1 Introduction 2 Experimental Setup 3 The Initial Ionization Process 4 The Characteristics of the Newly Formed Electron 5 The Fate of the Ion: Bond Softening 6 The Fate of the Ion: Enhanced Ionization 7 The Fate of the Electron: Measuring the Dynamics of Double Ionization 8 Conclusion References Probing Molecular Structure and Dynamics by Laser-Driven Electron Recollisions 1 Introduction 2 Laser-Driven Electron Dynamics Within an Optical Cycle 3 Signatures of Molecular Structure in the HHG Signal 4 Chirp-Encoded Measurements of Proton Dynamics in Molecules 5 Conclusion References Intense Laser Interaction with Noble Gas Clusters 1 Introduction 2 Experiments and Applications 3 Fundamental Concepts of Intense Laser-Cluster Interaction 3.1 Inner Ionization 3.2 Outer Ionization 3.3 Cluster Explosion 4 Electronic Heating Mechanisms 4.1 Collisional Heating 4.2 Nonlinear Cluster Heating 5 Collective Versus Collisional Phenomena 6 Conclusion References Laser-Induced Optical Breakdown in Solids 1 Introduction 2 Damage Induced by Nano- and Picosecond Pulses 3 Damage Induced by Femtosecond Laser Pulses 4 Light-Matter Interaction 4.1 Photoionization 4.2 Impact Ionization 4.3 Scaling Laws 4.4 Multiple Pulse Effects 5 Applications References Part 3: Laser-Driven X-ray Sources Macroscopic Effects in High-Order Harmonic Generation 1 Introduction 2 Propagation Equations 3 Main Propagation Effects 3.1 Absorption 3.2 Phase Matching 3.2.1 Dipole Phase 3.2.2 Geometric Dispersion 3.2.3 Atomic Dispersion 3.2.4 Electronic Dispersion 3.2.5 Generalized Phase-Matching Condition 3.3 Amplification 4 Optimal Generating Conditions 5 Influence on the Macroscopic Properties 6 Few-Cycle Laser Pulse (Non-adiabatic) Phenomena 7 Generation of Attosecond X-Ray Pulses 8 New Proposals for Phase Matching References Attosecond Pulses: Generation, Detection, and Applications 1 Introduction 2 Ultrashort Time Structures in the Non-linear Response 2.1 High Harmonic Generation 3 Propagation Effects 4 Attosecond Pulse Measurements 4.1 Interference of Two-Photon Transitions 4.2 Attosecond Streak Camera Techniques 4.3 Gating by the Laser Field 4.4 Experiments 4.4.1 A RABITT Measurement 4.4.2 Attosecond Streak Camera Measurements 5 Applications 5.1 Quantum Beats of Low-Lying States 5.2 Time-Domain Observation of an Auger Decay 5.3 Ionization Dynamics Experiments 5.4 Trains of Attosecond Pulses 6 Perspectives References High-Order Harmonics from Plasma Surfaces 1 Introduction 2 Modeling of High-Order Harmonic Generation 2.1 Oscillating Mirror Model 2.2 Oscillations of the Plasma Surface 2.3 Frequency Spectrum of the Emission from the Plasma Surface 2.4 The Time Domain Picture: Generation of Attosecond Pulses 2.5 PIC Simulations 3 Experimental Observations of HOHG 3.1 Harmonic Spectra, Divergence, and Conversion Efficiency 3.2 Influence of the Plasma Scale Length 4 Summary References Table-Top X-Ray Lasers in Short Laser Pulse and Discharge Driven Plasmas 1 Introduction 1.1 General Properties of X-Ray Lasers 1.1.1 Amplified Spontaneous Emission 1.1.2 Gain Medium 1.1.3 Emission Wavelength 1.1.4 Population Inversion/Gain 1.1.5 Intensity 1.1.6 Saturation 1.1.7 Pump Power Requirements for Soft X-Ray Lasers in Plasmas 1.1.8 Size and Geometrical Output Characteristics 1.1.9 Efficiency/Output Power/Energy 1.1.10 Linewidth 1.1.11 Pulse Duration 1.1.12 Coherence Spatial Coherence Temporal Coherence 1.1.13 Refraction 1.1.14 General Kinetics of Active Medium: Steady-State - Transient State Approach 1.1.15 The Steady-State, Quasi-steady-state and Transient Approximation 2 Excitation Mechanisms 2.1 Collisional XRLs 2.1.1 Ne-Like and Ni-Like Schemes Ne-Like Scheme Ni-Like Scheme 2.1.2 Realization of Transient Collisionally Pumped X-Ray Lasers Transient Excitation Scheme Travelling Wave Pumping Gas Puff Fast Discharge Capillary Hybrid Pumping of Capillary 2.2 Recombination XRL 2.2.1 General Features 2.2.2 Realization of Recombination Pumped X-Ray Lasers 2.3 Optical-Field Ionization Excitation 2.3.1 General Features 2.3.2 Propagation Issues in OFI-XRL 2.3.3 OFI with Linearly Polarized Pump Pulse-Recombination Excited XRL Realization of OFI-Recombination X-Ray Lasers 2.3.4 OFI with Circularly Polarized Pump Pulse-Collisional XRL Realization of OFI-Driven Collisional X-Ray Lasers 2.4 Inner-Shell-Excitation/Photoionization 2.5 Photoresonant Pumping 2.6 Recent Developments 2.6.1 Soft X-Ray Lasers in GRIP Geometry 2.6.2 XMOPA 3 Applications 3.1 Diagnostics with XRL 3.2 Interferometry 3.3 Reflectometry 3.4 Excitation of Nonlinear Processes References Time-Resolved X-Ray Science: Emergence of X-Ray Beams Using Laser Systems 1 Introduction 2 Laser-Based X-Ray Beam 2.1 Principle 2.2 Experiments 2.3 Comparison with Other Ultrafast X-Ray Sources 3 Conclusion References Atomic Multi-photon Interaction with Intense Short-Wavelength Fields 1 Introduction 2 Parameters Characterizing Intense-Field Dynamics 3 Lowest (Non-vanishing) Order Perturbation Theory: LOPT 4 A Finite-Sum Approximation to Green’s Function of Complex Atoms 5 Coulomb-Volkov Wavefunctions 5.1 An Asymptotic Coulomb-Volkov Wavefunction 5.2 An Adiabatic Coulomb-Volkov Wavefunction 5.3 A Semiclassical Coulomb-Volkov Wavefunction 5.4 Coulomb-Volkov Green’s Function 5.5 Approximate Coulomb-KFR Wavefunctions 5.6 Signature of Photon Thresholds in the ‘Tunnel Regime’ 5.7 High Harmonic Generation Under Adiabatic Condition 6 Oscillating K-H Frame 6.1 A High-Frequency Approximation for High Harmonic Generation 7 Numerical Methods in K-H Frame 8 Reduction of the Retardation Problem: A Modified Floquet Expansion 9 Relativistic Domain 10 Reduction of Retardation: Reduced Floquet-Dirac Equation 11 Super-Intense Fields: Spin Dynamics 12 Spin-Flip and Spin Asymmetry in Ionization 13 Summary References Part 4: Laser-Matter Interaction - Relativistic Relativistic Laser-Plasma Physics 1 Introduction 2 Free Electron Motion in Electromagnetic Wave. Relativistic Threshold 3 Relativistic Similarity 4 Numerical Simulation of Relativistic Laser-Plasma. Particle-in-Cell Method 5 Relativistic Self-Channeling of Light in Plasmas 6 Multiple Filamentation of Wide Laser Pulses 7 Direct Laser Acceleration of Electrons in Plasma Channels 8 Laser Wake Field Acceleration 9 3D Regime of Relativistic LWFA: The Bubble 10 Scaling Laws for the Bubble Regime of Electron Acceleration 11 The Breakthrough Experiments: Quasi-monoenergetic Electron Beams 12 X-Ray Generation in Strongly Non-linear Plasma Waves 13 Conclusions References High-Density Plasma Laser Interaction 1 Introduction 2 Linear Response Theory 3 Applications 3.1 Bremsstrahlung 3.2 Reflectivity 3.3 Thomson Scattering 4 Nonlinear Collisional Absorption References Relativistic Laser-Atom Physics 1 Introduction 2 Atomic Photoionization in the Relativistic Regime 3 Numerical Resolution of the Dirac Equation: A Paradigm for Lattice Fermion Field Physics 3.1 Spin Effects 3.2 ‘‘Zitterbewegung’’ 3.3 Pair Production 3.4 Tunneling Time(s)? 3.5 Cycloatoms 3.6 Two-Photon Bound-Bound Transitions 3.7 Radiation Reaction 4 Conclusions and Perspectives References Tests of QED with Intense Lasers 1 Introduction 2 Multiphoton Compton Scattering and Multiphoton Pair Production 3 Experimental Arrangement 4 Results on Multiphoton Compton Scattering 5 Results on e+e- Pair Production 6 Discussion References Nuclear Physics with Intense Lasers 1 Introduction 2 Production of High-Energy Electrons and gamma-Rays 3 Production of High-Energy Protons 4 Models of Proton and Ion Acceleration 5 Applications of Laser-Produced Proton Beams 6 Production of Neutrons 7 Neutron Spectroscopy in Ultra-intense Laser-Matter Interactions 8 Conclusions and Future Outlook References Part 5: Intense Field Physics with Heavy Ions Ion-Generated, Attosecond Pulses: Interaction with Atoms and Comparison to Femtosecond Laser Fields 1 Introduction 2 Interaction of Ion-Generated Pulses with Atoms 2.1 Introduction 2.2 Ion-Generated Fields and Comparison to Laser Fields 2.3 Single Ionization in As Fields: Connection to Photoionization 2.3.1 Small Perturbations (Single Photon Exchange) 2.3.2 Large Perturbations 2.4 Double Ionization 2.5 Summary 3 Many-Particle Momentum Spectroscopy of Ions and Electrons 4 Results 4.1 Single Ionization Dynamics in Perturbative As Pulses 4.2 Single Ionization Dynamics in Non-perturbative As Pulses 4.3 Double Ionization in Perturbative Collisions 4.4 Double Ionization at Strong Perturbation 4.5 Multiple Ionization in Attosecond Fields 5 A View into the Future 5.1 Experiments in Storage Rings 5.2 Laser-Assisted Collisions 5.3 VUV- and X-Ray Free Electron Lasers (SASE-FELs) References Index