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arXiv · 2104.05747

Spectrally resolved linewidth enhancement factor of a semiconductor frequency comb

Nikola Opačak·Florian Pilat·Dmitry Kazakov·Sandro Dal Cin·Georg Ramer·Bernhard Lendl·Federico Capasso·Benedikt Schwarz
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Abstract

The linewidth enhancement factor (LEF) has recently moved into the spotlight of research on frequency comb generation in semiconductor lasers. Here we present a novel modulation experiment, which enables the direct measurement of the spectrally resolved LEF in a laser frequency comb. By utilizing a phase-sensitive technique, we are able to extract the LEF for each comb mode. We first investigate and verify this universally applicable technique using Maxwell-Bloch simulations and then present the experimental demonstration on a quantum cascade laser frequency comb.

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Nikola Opačak, Florian Pilat, Dmitry Kazakov, Sandro Dal Cin, Georg Ramer, Bernhard Lendl, Federico Capasso, Benedikt Schwarz. 2021-04-12. Spectrally resolved linewidth enhancement factor of a semiconductor frequency comb. https://arxiv.org/abs/2104.05747

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