title: Suppression of stimulated Raman scattering employing long period gratings in double-clad fiber amplifiers.
abstract: We report on the suppression of stimulated Raman scattering (SRS) in a double-clad fiber amplifier using long-period gratings (LPGs). The LPGs, fabricated with a CO(2) laser, achieve SRS suppression by coupling the Stokes wavelength from the active core into the cladding. With only three LPGs inserted into a fiber pulse amplifier, the extractable Raman-free output power was nearly doubled. A numerical simulation of the setup shows good agreement with the experimental results.
authors.affiliation: Institute of Applied Physics, Friedrich-Schiller-University Jena, Albert-Einstein-Strasse 15, 07745 Jena, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Nodop
authors.forename: C
authors.initials: C
authors.lastname: Jauregui
authors.forename: F
authors.initials: F
authors.lastname: Jansen
authors.forename: J
authors.initials: J
authors.lastname: Limpert
authors.forename: A
authors.initials: A
authors.lastname: Tünnermann