Optics Letters

Interferometry and coherence of nonstationary light

Matias Koivurova, Lutful Ahad, Gianluca Geloni, Tero Setälä, Jari P. Turunen, Ari T. Friberg

Published Jan 15, 2019• 8 citations

Abstract

We consider temporally integrating interferometric measurements and their relation to the coherence properties of nonstationary light. We find that performing such experiments as a function of time delay is equivalent to spectrally resolving the interference patterns, and time-domain coherence information can be obtained from field autocorrelation only if the source is of the Schell-model type. In an analogy to autocorrelation, we introduce field cross-correlation, which can be used to determine the complete complex field of unknown signal pulses if suitable probe pulses are available. We demonstrate our findings with simulated supercontinuum and free-electron laser ensembles, and discuss the prospect of carrying out experiments.

DOI: 10.1364/ol.44.000522

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