title: Timing characterization of 100 GHz passively mode-locked discrete mode laser diodes.
abstract: We report on the characterization of the timing stability of passively mode-locked discrete mode diode laser sources. These are edge-emitting devices with a spatially varying refractive index profile for spectral filtering. Two devices with a mode-locking frequency of 100 GHz are characterized. The first device is designed to support a comb of six modes and generates near Fourier limited 1.9 ps pulses. The second supports four primary modes resulting in a sinusoidal modulation of the optical intensity. Using a cross-correlation technique, we measured a 20 fs pulse to pulse timing jitter for the first device, while, for the second device, a mode-beating (RF) linewidth of 1 MHz was measured using heterodyne mixing in a semiconductor optical amplifier. Comparison of these results with those obtained for an equivalent Fabry-Perot laser indicates that the spectral filtering mechanism employed does not adversely affect the timing properties of these passively mode-locked devices.
authors.affiliation: Tyndall National Institute, University College Cork, Lee Maltings, Cork, Ireland. david.bitauld@tyndall.ie
authors.forename: David
authors.initials: D
authors.lastname: Bitauld
authors.forename: Simon
authors.initials: S
authors.lastname: Osborne
authors.forename: Stephen
authors.initials: S
authors.lastname: O'Brien