Harmonic mode locking in a high-Q whispering gallery mode microcavity

Takasumi Tanabe, Takumi Kato, Tomoya Kobatake, Ryo Suzuki, Akitoshi Chen-Jinnai

Research output: Chapter in Book/Report/Conference proceedingConference contribution


We present a numerical and experimental study of the generation of harmonic mode locking in a silica toroid microcavity. We use a generalized mean-field Lugiato-Lefever equation and solve it with the split-step Fourier method. We found that a stable harmonic mode-locking regime can be accessed when we reduce the input power after strong pumping even if we do not carefully adjust the wavelength detuning. This is due to the bistable nature of the nonlinear cavity system. The experiment agrees well with the numerical analysis, where we obtain a low-noise Kerr comb spectrum with a narrow longitudinal mode spacing by gradually reducing the input pump power after strong pumping. This finding clarifies the procedure for generating harmonic mode locking in such high-Q microcavity systems.

Original languageEnglish
Title of host publicationLaser Resonators, Microresonators, and Beam Control XVIII
EditorsAlexis V. Kudryashov, Alan H. Paxton, Vladimir S. Ilchenko, Lutz Aschke
ISBN (Electronic)9781628419627
Publication statusPublished - 2016
EventLaser Resonators, Microresonators, and Beam Control XVIII - San Francisco, United States
Duration: 2016 Feb 152016 Feb 18

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X


OtherLaser Resonators, Microresonators, and Beam Control XVIII
Country/TerritoryUnited States
CitySan Francisco


  • Kerr comb
  • Whispering gallery mode
  • all-optical switching
  • microcavity
  • mode locking
  • optical nonlinearity

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Harmonic mode locking in a high-Q whispering gallery mode microcavity'. Together they form a unique fingerprint.

Cite this