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arXiv · 2204.02564

Low phase noise THz generation from a fiber-referenced Kerr microresonator soliton comb

Naoya Kuse·Kenji Nishimoto·Yu Tokizane·Shota Okada·Gabriele Navickaite·Michael Geiselmann·Kaoru Minoshima·Takeshi Yasui
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Abstract

THz oscillators generated via frequency-multiplication of microwaves are facing difficulty in achieving low phase noise. Photonics-based techniques, in which optical two tones are translated to a THz wave through opto-electronic conversion, are promising if the relative phase noise between the two tones is well suppressed. Here, a THz ($\approx$ 560 GHz) wave with a low phase noise is provided by a frequency-stabilized, dissipative Kerr microresonator soliton comb. The repetition frequency of the comb is stabilized to a long fiber in a two-wavelength delayed self-heterodyne interferometer, significantly reducing the phase noise of the THz wave. A measurement technique to characterize the phase noise of the THz wave beyond the limit of a frequency-multiplied microwave is also demonstrated, showing the superior phase noise of the THz wave to any other photonic THz oscillators (> 300 GHz).

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Naoya Kuse, Kenji Nishimoto, Yu Tokizane, Shota Okada, Gabriele Navickaite, Michael Geiselmann, Kaoru Minoshima, Takeshi Yasui. 2022-04-06. Low phase noise THz generation from a fiber-referenced Kerr microresonator soliton comb. https://doi.org/10.1038/s42005-022-01100-0

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