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arXiv · 1208.4155

Mid-infrared supercontinuum generation in tapered chalcogenide fiber for producing octave-spanning frequency comb around 3 {\mu}m

Alireza Marandi·Charles W. Rudy·Victor G. Plotnichenko·Evgeny M. Dianov·Konstantin L. Vodopyanov·Robert L. Byer
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Abstract

We demonstrate mid-infrared (mid-IR) supercontinuum generation (SCG) with instantaneous bandwidth from 2.2 to 5 {\mu}m at 40 dB below the peak, covering the wavelength range desirable for molecular spectroscopy and numerous other applications. The SCG occurs in a tapered As2S3 fiber prepared by in-situ tapering and is pumped by femtosecond pulses from the subharmonic of a mode-locked Er-doped fiber laser. Interference with a narrow linewidth c.w. laser verifies that the coherence properties of the near-IR frequency comb have been preserved through these cascaded nonlinear processes. With this approach stable broad mid-IR frequency combs can be derived from commercially available near-IR frequency combs without an extra stabilization mechanism.

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Alireza Marandi, Charles W. Rudy, Victor G. Plotnichenko, Evgeny M. Dianov, Konstantin L. Vodopyanov, Robert L. Byer. 2012-08-21. Mid-infrared supercontinuum generation in tapered chalcogenide fiber for producing octave-spanning frequency comb around 3 {\mu}m. https://doi.org/10.1364/oe.20.024218

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