Phase-stabilized Ultrashort Laser Systems for Spectroscopy

Inhaltsverzeichnis (Table of Contents)

• Zusammenfassung
• Abstract
• 1 Introduction
  • 1.1 Time-resolved spectroscopy
  • 1.2 Optical frequency metrology with frequency combs
• 2 Ultra-broadband oscillators
  • 2.1 Few-cycle Kerr-lens mode-locked Ti:sapphire oscillator
  • 2.2 Chirped mirror technology for dispersion control
  • 2.3 The carrier-envelope phase of a mode-locked oscillator
    • 2.3.1 Measurement of the frequency comb parameters
    • 2.3.2 CE phase stabilization by difference frequency generation
    • 2.3.3 Control of the frequency comb parameters
    • 2.3.4 CE phase stability characterization
  • 2.4 Long-cavity chirped-pulse oscillators
    • 2.4.1 Double-pass post-amplifier
  • 2.5 Conclusions
• 3 Few-cycle chirped-pulse amplifier systems
  • 3.1 CE phase-stabilized chirped-pulse amplifier system
    • 3.1.1 Origins of CE phase noise of amplified pulses
  • 3.2 Conclusions
• 4 Femtosecond enhancement cavities
  • 4.1 Passive optical resonators for femtosecond pulses
    • 4.1.1 Dispersion control
    • 4.1.2 Electronic feedback techniques
  • 4.2 Vacuum enhancement cavity at 10 MHz repetition rate
  • 4.3 Conclusions
• 5 Applications
  • 5.1 Spectroscopy experiments with frequency combs
  • 5.2 High-order harmonic generation
    • 5.2.1 High harmonic generation from surfaces
    • 5.2.2 High-order harmonic generation in an enhancement cavity
  • 5.3 Above-threshold ionization
  • 5.4 Conclusions
• 6 Outlook

Zielsetzung und Themenschwerpunkte (Objectives and Key Themes)

This thesis presents the development and characterization of several ultrafast laser sources for time-resolved spectroscopy and optical frequency metrology. The primary objective is to achieve high-precision control over the carrier-envelope phase of few-cycle laser pulses. This control enables the study of strong-field phenomena that are highly sensitive to the waveform of the electric field.

• Phase stabilization of ultra-broadband laser oscillators
• Preservation of CE phase stability during amplification
• Development of enhancement cavities for femtosecond pulses
• Applications of phase-stabilized few-cycle pulses in time-resolved spectroscopy and frequency metrology
• High-harmonic generation from surfaces and within enhancement cavities

Zusammenfassung der Kapitel (Chapter Summaries)

• Chapter 1 introduces the research fields motivating the construction of the laser sources. This chapter discusses the importance of time-resolved spectroscopy and optical frequency metrology for exploring fundamental processes in matter.
• Chapter 2 presents various ultra-broadband laser oscillators, including a novel technique for stabilizing the carrier-envelope phase. This chapter also describes the development and implementation of chirped mirrors for dispersion control.
• Chapter 3 discusses the construction of a few-cycle chirped-pulse amplifier system with preserved CE phase stability. This chapter delves into the origins of CE phase noise in amplifier systems.
• Chapter 4 presents the design and setup of femtosecond enhancement cavities operating at 10 MHz and 100 MHz repetition rates. This chapter discusses the challenges of supporting the broad bandwidth of femtosecond pulses in optical resonators, including dispersion control and electronic feedback techniques.
• Chapter 5 focuses on applications of the developed laser sources. This chapter includes examples of spectroscopy experiments with frequency combs, as well as investigations of strong-field phenomena driven by intense few-cycle pulses, such as high-order harmonic generation from surfaces and within enhancement cavities, and above-threshold ionization.
• Chapter 6 provides an outlook on future research directions in the field of ultrafast laser science, highlighting the potential of enhancement cavities and Yb-based amplifier systems for advancing spectroscopy and frequency metrology in the XUV region.

Schlüsselwörter (Keywords)

This thesis is focused on phase-stabilized ultrafast laser systems for spectroscopy. Key terms include few-cycle laser pulses, carrier-envelope phase, frequency combs, high-order harmonic generation, above-threshold ionization, enhancement cavities, time-resolved spectroscopy, optical frequency metrology, and XUV spectroscopy.