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arXiv · 0707.0435

Spectrally resolved optical frequency comb from a self-referenced 5 GHz femtosecond laser

Albrecht Bartels·Raphael Gebs·Matt Kirchner·Scott A. Diddams
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Abstract

We report a mode-locked Ti:sapphire femtosecond laser with 5GHz repetition rate. Spectral broadening of the 24 fs pulses in a microstructured fiber yields an octave-spanning spectrum and permits self-referencing and active stabilization of the emitted femtosecond laser frequency comb (FLFC). The individual modes of the 5GHz FLFC are resolved with a high-resolution spectrometer based on a virtually imaged phased array (VIPA) spectral disperser. Isolation of single comb elements at a microwatt average power level is demonstrated. The combination of the high-power, frequency-stabilized 5GHz laser and the straightforward resolution of its many modes will benefit applications in direct frequency comb spectroscopy. Additionally, such a stabilized FLFC should serve as a useful tool for direct mode-by-mode Fourier synthesis of arbitrary optical waveforms.

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Albrecht Bartels, Raphael Gebs, Matt Kirchner, Scott A. Diddams. 2007-07-03. Spectrally resolved optical frequency comb from a self-referenced 5 GHz femtosecond laser. https://doi.org/10.1364/ol.32.002553

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