title: Low-pump-power, short-fiber copropagating dual-pumped (800 and 1050 nm) thulium-doped fiber amplifier.
abstract: Using optical frequency-domain reflectometry to reveal the gain distribution and allow us to optimize a thulium-doped fiber amplifier, we have demonstrated 18-dB gain by employing only 5 m of a 2000-parts-in-10(6)-Tm-doped fiber pumped with 145 mW of power at dual wavelengths of 800 and 1050 nm. The role of the 800-nm pump, which by itself does not permit population inversion, was clearly observed experimentally.
authors.affiliation: Departamento de Física, Universidade Federal de Pernambuco, Cidade Universitária, 50670-901, Recife, PE, Brazil. anderson@df.ufpe.br
authors.forename: A S L
authors.initials: AS
authors.lastname: Gomes
authors.forename: M T
authors.initials: MT
authors.lastname: Carvalho
authors.forename: M L
authors.initials: ML
authors.lastname: Sundheimer
authors.forename: C J A
authors.initials: CJ
authors.lastname: Bastos-Filho
authors.forename: J F
authors.initials: JF
authors.lastname: Martins-Filho
authors.forename: J P
authors.initials: JP
authors.lastname: Von der Weid
authors.forename: W
authors.initials: W
authors.lastname: Margulis