title: Narrow-linewidth, multi-Watt Yb-doped fiber amplifier at 1014.8 nm.
abstract: We report on an efficient, narrow linewidth, two-stage fiber amplifier at 1014.8 nm based on Yb-doped double-clad fibers. The fibers are cooled to liquid-nitrogen temperatures in order to suppress absorption at the operating wavelength. We achieved output powers of up to 5.0 W at a linewidth of less than 3 MHz by seeding the amplifier with the radiation from an external cavity diode laser.
authors.affiliation: Institute of Applied Physics, TU Darmstadt, Darmstadt, Germany.
authors.forename: Albert
authors.initials: A
authors.lastname: Seifert
authors.forename: Mathias
authors.initials: M
authors.lastname: Sinther
authors.forename: Thomas
authors.initials: T
authors.lastname: Walther
authors.forename: Edward S
authors.initials: ES
authors.lastname: Fry