title: Coherently combined fiber laser system delivering 120 μJ femtosecond pulses.
abstract: We report on the coherent combination of two chirped pulsed fiber lasers. The beams coming from two 100 μm core diameter ytterbium-doped rod-type fibers were coupled in a Mach-Zehnder-type interferometer by means of a polarization beam splitter. Active stabilization of the interferometer was achieved by using a piezo-mounted mirror driven by a Hänsch-Couillaud polarization detection system. Pulses with 120 μJ energy and a compressed duration of 800 fs were obtained. This, compared with the 66 μJ coming from each single amplifier, results in a combining efficiency as high as 91%.
authors.affiliation: Institute of Applied Physics, Friedrich Schiller University Jena, Jena, Germany. enrico.seise@uni‑jena.de
authors.forename: Enrico
authors.initials: E
authors.lastname: Seise
authors.forename: Arno
authors.initials: A
authors.lastname: Klenke
authors.forename: Sven
authors.initials: S
authors.lastname: Breitkopf
authors.forename: Marco
authors.initials: M
authors.lastname: Plötner
authors.forename: Jens
authors.initials: J
authors.lastname: Limpert
authors.forename: Andreas
authors.initials: A
authors.lastname: Tünnermann