We report on the destabilization of the mode-locking operation of a long cavity fiber laser. We show that the destabilization is accompanied by the abrupt emergence of a strong frequency-downshifted Stokes signal, and simultaneously, we find that the laser output displays characteristics typical of noise-like pulses. We use numerical simulations to illustrate how the Stokes signal grows from stimulated Raman scattering and plays a key role in the destabilization of the laser output. Our results indicate that stimulated Raman scattering may impose an ultimate limit on the energy scalability via cavity lengthening.
© 2013 Optical Society of America
Original Manuscript: April 11, 2013
Revised Manuscript: June 7, 2013
Manuscript Accepted: June 24, 2013
Published: July 18, 2013
Claude Aguergaray, Antoine Runge, Miro Erkintalo, and Neil G. R. Broderick, "Raman-driven destabilization of mode-locked long cavity fiber lasers: fundamental limitations to energy scalability," Opt. Lett. 38, 2644-2646 (2013)