title: Spatial decoherence of pulsed broad-area vertical-cavity surface-emitting lasers.
abstract: We report a strong reduction of spatial coherence of the emission of large aperture vertical-cavity surface-emitting lasers when they are driven by microsecond electrical pulses. We give evidence that this is due to a breakdown of the modal emission of these lasers. The spatial decoherence manifests itself in the formation of a Gaussian far field intensity distribution. The coherence radius we extract is 1.4 micrometer under these operating conditions, irrespective of the Fresnel number of the vertical-cavity surface-emitting laser. Finally, the spatial coherence properties can be varied by changing the pulse duration or pulse amplitude.
authors.forename: Michael
authors.initials: M
authors.lastname: Peeters
authors.forename: Guy
authors.initials: G
authors.lastname: Verschaffelt
authors.forename: Hugo
authors.initials: H
authors.lastname: Thienpont
authors.forename: Shyam
authors.initials: S
authors.lastname: Mandre
authors.forename: Ingo
authors.initials: I
authors.lastname: Fischer
authors.forename: Martin
authors.initials: M
authors.lastname: Grabherr