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Tapered semiconductor amplifiers for optical frequency combs in the near infrared

Flavio C. Cruz·Matthew C. Stowe·Jun Ye
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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 over 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 with very limited power in the infrared.

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Flavio C. Cruz, Matthew C. Stowe, Jun Ye. 2006-02-15. Tapered semiconductor amplifiers for optical frequency combs in the near infrared. https://doi.org/10.1364/ol.31.001337

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