title: Phase-locked two-branch erbium-doped fiber laser system for long-term precision measurements of optical frequencies.
abstract: We present a highly versatile approach to the application of femtosecond Er:fiber lasers in optical frequency metrology. Our concept relies on the implementation of two parallel amplifiers, seeded by a single master oscillator. With the comb spacing locked to a frequency of 100 MHz, we apply the output from the first amplifier to generate a feedback signal to achieve a simultaneous phase-lock for the comb offset frequency. The output of the independently configurable second amplifier enables precision frequency measurements in the visible and near-infrared. As a first application, we continuously measure the absolute frequency of a resonator-stabilized diode laser over a period of 88 hours.
authors.forename: Florian
authors.initials: F
authors.lastname: Adler
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Moutzouris
authors.forename: Alfred
authors.initials: A
authors.lastname: Leitenstorfer
authors.forename: Harald
authors.initials: H
authors.lastname: Schnatz
authors.forename: Burghard
authors.initials: B
authors.lastname: Lipphardt
authors.forename: Gesine
authors.initials: G
authors.lastname: Grosche
authors.forename: Florian
authors.initials: F
authors.lastname: Tauser