A new technique is proposed and demonstrated for reducing the timing jitter of a mode-locked laser diode by use of fiber-optic interferometers with an optical path difference much longer than the laser’s coherence length. At the output of the interferometer the intensities of the two pulse trains are incoherently added, giving rise to the cancellation of timing noise at specific Fourier frequencies determined by the path difference. The timing jitter of pulse trains emitted by a 19.444-GHz mode-locked laser is reduced to 0.991 and 0.874 ps for 100-kHz–18-MHz bandwidth after the pulse trains pass through a cascaded Mach–Zehnder and a ring interferometer, respectively.
© 2003 Optical Society of America
(140.2020) Lasers and laser optics : Diode lasers
(140.4050) Lasers and laser optics : Mode-locked lasers
(140.7090) Lasers and laser optics : Ultrafast lasers
(320.7090) Ultrafast optics : Ultrafast lasers
(320.7160) Ultrafast optics : Ultrafast technology
Hidemi Tsuchida, "Pulse timing-jitter reduction by incoherent addition," Opt. Lett. 28, 474-476 (2003)