title: Two-time coherence of pulse trains and the integrated degree of temporal coherence.
abstract: We examine the temporal coherence properties of trains of nonidentical short optical pulses in the framework of the second-order coherence theory of nonstationary light. Considering Michelson's interferometric measurement of temporal coherence, we demonstrate that time-resolved interferograms reveal the full two-time temporal coherence function of the partially coherent pulse train. We also show that the result given by the time-integrated Michelson interferogram equals the true degree of temporal coherence only when the pulse train is quasi-stationary, i.e., the coherence time is a small fraction of the pulse duration. True two-time and integrated coherence functions produced by specific models representing perturbed trains of mode-locked pulses and supercontinuum pulse trains produced in nonlinear fibers are illustrated.
authors.forename: Rahul
authors.initials: R
authors.lastname: Dutta
authors.forename: Ari T
authors.initials: AT
authors.lastname: Friberg
authors.forename: Göery
authors.initials: G
authors.lastname: Genty
authors.forename: Jari
authors.initials: J
authors.lastname: Turunen