Interferometry and coherence of nonstationary light

Area of Science:

• Quantum Optics and Photonics
• Coherence Theory
• Interferometry

Background:

• Understanding the coherence properties of nonstationary light is crucial for advanced optical applications.
• Traditional methods often rely on spectral analysis, limiting time-domain characterization.
• The relationship between temporal integration and spectral resolution in interferometry needs further exploration.

Purpose of the Study:

• To investigate the connection between temporally integrating interferometric measurements and the coherence of nonstationary light.
• To introduce and validate a new method for complete complex field determination of optical pulses.
• To explore the potential for new experimental techniques in optical pulse characterization.

Main Methods:

• Analysis of temporally integrating interferometric measurements as a function of time delay.
• Comparison with spectral resolution of interference patterns.
• Introduction and theoretical development of field cross-correlation as an analogue to autocorrelation.
• Simulations using supercontinuum and free-electron laser ensembles.

Main Results:

• Temporally integrating interferometric experiments are equivalent to spectrally resolving interference patterns.
• Time-domain coherence information is obtainable via field autocorrelation only for Schell-model sources.
• Field cross-correlation enables the determination of the complete complex field of unknown signal pulses using probe pulses.

Conclusions:

• The study establishes a direct link between time-domain interferometry and spectral analysis for nonstationary light.
• Field cross-correlation offers a powerful new tool for full optical pulse characterization.
• The findings pave the way for novel experimental approaches in ultrafast optics and coherent control.