Ultrafast Supercontinuum Generation in Transparent Solid-State Media (eBook)

Audrius Dubietis graduated from Vilnius University in 1989, and was awarded a PhD in 1996. He has been professor in the Department of Quantum Electronics, Laser Research Center, Vilnius University, since 2006. His areas of research areas include nonlinear optics, laser physics, atmospheric phenomena, physics, optics, and astronomy. In 1992, together with G. Jonušauskas and A. Piskarskas, he proposed a method of parametric amplification of phase-modulated light pulses, which is implemented by the most important ultra-powerful laser centers worldwide. He has published more than 90 scientific articles in the peer-reviewed literature.Arnaud Couairon is a research director at the CNRS. He studied at Ecole Normale Supérieure in Paris and did his Ph.D. at Ecole Polytechnique (1997) on the dynamics of open shear flows. Since 1997, he has been working on ultrashort laser pulse filamentation and associated phenomena. He developed a virtual numerical laboratory for simulating the nonlinear propagation of ultrashort laser pulses in gases, liquids, or solids. His research interests include laser-matter interaction, ultrafast and nonlinear optics, and plasma physics.

Preface 6
Acknowledgments 7
Contents 8
1 Introduction 10
References 12
Part I Physical Picture of Supercontinuum Generation 15
2 Governing Physical Effects 16
2.1 Self-focusing of Laser Beams 17
2.2 Self-phase Modulation of Laser Pulses 20
2.3 Nonlinear Absorption and Ionization 23
2.4 Plasma Effects 23
2.4.1 Transition of Electrons from the Valence to the Conduction Band 23
2.4.2 Refractive Index Change 24
2.4.3 Plasma-Induced Phase Modulation 24
2.4.4 The Drude–Lorentz Model 26
2.5 Intensity Clamping 27
2.6 Chromatic Dispersion 29
2.7 Self-steepening and Space-Time Focusing 31
2.8 Four-Wave Mixing and Phase Matching 31
References 32
3 Femtosecond Filamentation in Solid-State Media 34
3.1 Universal Features of Femtosecond Filamentation 35
3.1.1 Conical Emission 35
3.1.2 Plasma Channel Formation 35
3.1.3 Filament Robustness and Energy Reservoir 36
3.1.4 Conical Waves 37
3.2 Numerical Model 40
3.3 Supercontinuum Generation Under Normal GVD 45
3.4 Supercontinuum Generation in the Region of Anomalous GVD 46
3.5 Supercontinuum Generation Under Zero GVD 47
3.6 Conical Emission 48
References 50
Part II Overview of the Experimental Results 54
4 General Practical Considerations 55
4.1 Materials 55
4.2 External Focusing 58
4.3 Stability Issues 62
4.4 Effect of Filament Refocusing 64
4.5 Multiple Filamentation 66
References 67
5 Experimental Results 70
5.1 Water as a Prototypical Nonlinear Medium 70
5.2 Glasses 72
5.3 Alkali Metal Fluorides 75
5.4 Laser Hosts 79
5.5 Crystals with Second-Order Nonlinearity 83
5.6 Semiconductors 87
5.7 Other Nonlinear Media 91
References 92
6 New Developments 100
6.1 Power and Energy Scaling 100
6.2 Extracavity Pulse Compression 103
6.2.1 Pulse Compression Exploiting SPM in Normally Dispersive Media 104
6.2.2 Soliton Compression Due to Second-Order Cascading 107
6.2.3 Self-compression Through Filamentation 108
6.2.4 Soliton Compression in Isotropic Nonlinear Media with Anomalous GVD 109
6.2.5 Other Compression Mechanisms 112
6.3 Supercontinuum Generation with Picosecond Laser Pulses 113
6.4 Control of Supercontinuum Generation 117
6.5 Supercontinuum Generation with Non-Gaussian Beams 121
6.6 Other Developments 123
References 124