The impact of self-phase modulation on coherently combined ultrafast fiber-based chirped-pulse amplifiers (CPA) is studied. We point out that, in nonlinear CPA regime, the nonlinear phase accumulated in each fiber amplifier can significantly differ from one to another, resulting in serious efficiency degradation of coherent combining. A test bench based on picosecond pulses, and a single fiber amplifier is developed to experimentally demonstrate the effect. The effects that can lead to this nonlinear phase deviation and the induced system limitations are discussed and analyzed.
© 2010 Optical Society of America
Lasers and Laser Optics
Original Manuscript: January 26, 2010
Revised Manuscript: March 11, 2010
Manuscript Accepted: March 12, 2010
Published: April 15, 2010
Shifeng Jiang, Marc Hanna, Frédéric Druon, and Patrick Georges, "Impact of self-phase modulation on coherently combined fiber chirped-pulse amplifiers," Opt. Lett. 35, 1293-1295 (2010)