title: Tapered semiconductor amplifiers for optical frequency combs in the near infrared.
abstract: A tapered semiconductor amplifier is injection seeded by a femtosecond optical frequency comb at 780 nm from a mode-locked Ti:sapphire laser. Energy gains of more than 17 dB(12 dB) are obtained for 1 mW(20 mW) of average input power when the input pulses are stretched into the picosecond range. A spectral window of supercontinuum light generated in a photonic fiber has also been amplified. Interferometric measurements show sub-Hertz linewidths for a heterodyne beat between the input and amplified comb components, yielding no detectable phase-noise degradation under amplification. These amplifiers can be used to boost the infrared power in f-to-2f interferometers used to determine the carrier-to-envelope offset frequency, with clear advantages for stabilization of octave-spanning femtosecond lasers and other supercontinuum light sources.
authors.affiliation: JILA, National Institute of Standards and Technology, Colorado 80309-0440, USA. flavio@ifi.unicamp.br
authors.forename: Flavio C
authors.initials: FC
authors.lastname: Cruz
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Stowe
authors.forename: Jun
authors.initials: J
authors.lastname: Ye