We measured the optical linewidths of a passively mode-locked quantum dot laser and show that, in agreement with theoretical predictions, the modal linewidth exhibits a parabolic dependence with the mode optical frequency. The minimum linewidth follows a Schawlow-Townes behavior with a rebroadening at high power. In addition, the slope of the parabola is proportional to the RF linewidth of the laser and can therefore provide a direct measurement of the timing jitter. Such a measurement could be easily applied to mode-locked semiconductor lasers with a fast repetition rate where the RF linewidth cannot be directly measured.
Bibliographical note© 2009 Optical Society of America
T. Habruseva, S. O'Donoghue, N. Rebrova, F. Kéfélian, S. P. Hegarty, and G. Huyet, "Optical linewidth of a passively mode-locked semiconductor laser," Optics letters, 34, 3307-3309 (2009)
This paper was published in Optics letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/ol/abstract.cfm?URI=ol-34-21-3307 . Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.
Habruseva, T., O'Donoghue, S., Rebrova, N., Kéfélian, F., Hegarty, S. P., & Huyet, G. (2009). Optical linewidth of a passively mode-locked semiconductor laser. Optics Letters, 34(21), 3307-3309. https://doi.org/10.1364/OL.34.003307