Kerr-Nonlinearity-Induced Mode-Splitting in Optical Microresonators

George N. Ghalanos, Jonathan M. Silver, Leonardo Del Bino, Niall Moroney, Shuangyou Zhang, Michael T. M. Woodley, Andreas Ø. Svela, Pascal Del'Haye

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19 Citations (Scopus)
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The Kerr effect in optical microresonators plays an important role for integrated photonic devices and enables third harmonic generation, four-wave mixing, and the generation of microresonator-based frequency combs. Here we experimentally demonstrate that the Kerr nonlinearity can split ultra-high-Q microresonator resonances for two continuous-wave lasers. The resonance splitting is induced by self- and cross-phase modulation and counterintuitively enables two lasers at different wavelengths to be simultaneously resonant in the same microresonator mode. We develop a pump-probe spectroscopy scheme that allows us to measure power dependent resonance splittings of up to 35 cavity linewidths (corresponding to 52 MHz) at 10 mW of pump power. The required power to split the resonance by one cavity linewidth is only 286  μW. In addition, we demonstrate threefold resonance splitting when taking into account four-wave mixing and two counterpropagating probe lasers. These Kerr splittings are of interest for applications that require two resonances at optically controlled offsets, e.g., for optomechanical coupling to phonon modes, optical memories, and precisely adjustable spectral filters.

Original languageEnglish
Article number223901
JournalPhysical Review Letters
Issue number22
Early online date4 Jun 2020
Publication statusPublished - 5 Jun 2020

ASJC Scopus subject areas

  • General Physics and Astronomy


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