Table of contents : Supervisor’s Foreword Abstract Acknowledgements Contents List of Acronyms 1 Motivation 1.1 MIRanda–-A New Ultrafast Workhorse for Mid-Infrared Applications 1.2 The Power of Directly Diode-Pumped, Few-Cycle Mid-Infrared Lasers 1.3 Thesis Outline References 2 Fundamentals of Ultrashort Pulse Generation 2.1 Formation of Laser Pulses 2.1.1 Locking the Longitudinal Modes of a Laser Cavity 2.1.2 Experimental Realization Methods 2.2 Soliton Pulse Propagation 2.2.1 Dispersion 2.2.2 Self-Phase Modulation 2.2.3 The Fundamental Soliton 2.3 Soliton Mode-Locking 2.3.1 Gain, Loss, and the Spectral Filtering 2.3.2 Self-Amplitude Modulation 2.3.3 The Master Equation of Mode-Locking 2.3.4 The Effect of Different Dispersion Regimes 2.4 Summary References 3 The First Directly Diode-Pumped Few-Cycle Cr-Doped II-VI Laser 3.1 Chromium-Doped II-VI–-The Titanium Sapphire of the Mid-Infrared 3.2 Challenges of Diode-Pumping 3.2.1 The Right Choice of Laser Diode Type 3.2.2 Properties of Single-Emitter Diodes 3.2.3 Effects on the Laser System and the Few-Cycle Pulse Generation 3.3 Few-Cycle Pulse Generation via Kerr-Lens Mode-Locking 3.3.1 Pump Setup and Resonator Design 3.3.2 The Importance of Intra-cavity Dispersion Management 3.3.3 Characterization of the Mode-Locked Output 3.3.4 The Success of Powerful Diode-Pumped Operation 3.4 Summary References 4 Reaching the Performance of State-of-the-Art Fiber-Pumped Systems 4.1 Challenges of Reaching Higher Average and Peak Powers 4.1.1 Pump Setup Considerations 4.1.2 Effects on the Mode-Locking Performance 4.2 Comparison and Improvements over MIRanda1 4.2.1 Pump and Cavity Design 4.2.2 Mode-Locked Performance 4.3 Summary References 5 Pushing the Peak Power for Direct Mid-Infrared Generation 5.1 Challenges of Reaching Higher Peak Powers 5.2 Experimental Achievements 5.2.1 Pump and Oscillator Setup 5.2.2 Mode-Locked Performance and the Effect of Air Dispersion 5.2.3 Towards Even Higher Peak Power Levels 5.3 Frequency Down-Conversion into the Mid-Infrared 5.3.1 Intra-Pulse Difference Frequency Generation in a ZGP Crystal 5.3.2 Characterization of the Generated Radiation 5.4 Summary References 6 Conclusion and Outlook 6.1 Summary 6.2 A New Ultrafast Workhorse for Spectroscopic Applications? 6.3 Closing Remarks References Appendix A.1 Data Archiving A.2 Curriculum Vitae A.3 List of Publications