Gain-induced Kerr beam cleaning in a femtosecond fiber amplifier
Abstract
Kerr beam cleaning is a nonlinear phenomenon in graded-index multimode fiber where power flows toward the fundamental mode, generating bell-shaped output beams. Here we study beam cleaning of femtosecond pulses accompanied by gain in a multimode fiber amplifier. Mode-resolved energy measurements and numerical simulations showed that the amplifier generates beams with high fundamental mode content (greater than 30% of the overall pulse energy) for a wide range of amplification levels. Control experiments using stretched pulses that evolve without strong Kerr nonlinear effects showed a degrading beam profile, in contrast to nonlinear beam cleaning. Temporal measurements showed that seed pulse parameters have a strong effect on the amplified pulse quality. These results may influence the design of future high-performance fiber lasers and amplifiers.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 19, 2023
- Source ID
- 10.1364/josab.492262
Entities
People
- Anirban Dhar
- Demetrios N. Christodoulides
- Frank W Wise
- Henry Haig
- Nicholas Bender
- Nilotpal Choudhury
- Ranjan Sen
- Yihao Chen
Organizations
- Academy of Scientific and Innovative Research
- Cornell University
- National Science Foundation
- Office of Naval Research
- Simons Foundation
- University of Southern California