Dynamics of a Low-Dimensional Model for Short Pulse Mode Locking

• Main Authors: Edward D. Farnum, J. Nathan Kutz
• Format: Article
• Language: English
• Published: MDPI AG 2015-08-01
• Series: Photonics
• Subjects: mode-locked lasers; short pulse equation, ultra-fast optics
• Online Access: http://www.mdpi.com/2304-6732/2/3/865

Emerging ultra-fast mode-locked lasers are now capable of generating pulses in the few to sub-femtosecond regime. Using recent theoretical innovations around the short pulse equation, we characterize the mode locking dynamics using a low-dimensional representation of the pulse parameters. The theory is formulated using a variational approach, since linearization of the exact solution is not tractable. The dominant dynamics can be characterized in a geometrical way using phase-plane analysis. Of note is our ability to determine the underlying bifurcations that occur due to changes in the fiber laser cavity parameters, including the onset of the multi-pulsing instability. The theory can aid in design principles for generating robust and highly-stable mode-locked pulses.