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arXiv · 1010.2527

Bandwidth scaling and spectral flatness enhancement of optical frequency combs from phase modulated continuous-wave lasers using cascaded four-wave mixing

V. R. Supradeepa·Andrew M. Weiner
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Abstract

We introduce a new cascaded four-wave mixing technique which scales up the bandwidth of frequency combs generated by phase modulation of a continuous wave laser while simultaneously enhancing the spectral flatness. As a result we demonstrate a 10 GHz frequency comb with over 100 lines in a 10-dB bandwidth in which a record 75 lines are within a flatness of 1-dB. The cascaded four-wave mixing process increases the bandwidth of the initial comb generated by modulation of a CW laser by a factor of five. The broadband comb has approximately quadratic spectral phase, which is compensated upon propagation in single mode fiber, resulting in a 10 GHz train of 940 fs pulses

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V. R. Supradeepa, Andrew M. Weiner. 2012-11-09. Bandwidth scaling and spectral flatness enhancement of optical frequency combs from phase modulated continuous-wave lasers using cascaded four-wave mixing. https://doi.org/10.1364/ol.37.003066

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