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arXiv · 1712.04601

Transition between Kerr comb and stimulated Raman comb in a silica whispering gallery mode microcavity

Shun Fujii·Takumi Kato·Ryo Suzuki·Atsuhiro Hori·Takasumi Tanabe
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Abstract

We theoretically and experimentally investigated the transition between modulation instability and Raman gain in a small silica microcavity with a large free-spectral range (FSR), which reveals that we can selectively switch from a four-wave mixing dominant state to a stimulated Raman scattering dominant state. Both the theoretical analysis and the experiment show that a Raman-dominant region is present between transitions of Kerr combs with different free-spectral range spacings. We can obtain a stable Kerr comb and a stable Raman state selectively by changing the driving power, coupling between the cavity and the waveguide, and laser detuning. Such a controllable transition is achieved thanks to the presence of gain competition between modulation instability and Raman gain in silica whispering gallery mode microcavities.

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Shun Fujii, Takumi Kato, Ryo Suzuki, Atsuhiro Hori, Takasumi Tanabe. 2017-12-13. Transition between Kerr comb and stimulated Raman comb in a silica whispering gallery mode microcavity. https://doi.org/10.1364/josab.35.000100

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