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Updated: Jun 21, 2026

Rapid Repetition Rate Fluctuation Measurement of Soliton Crystals in a Microresonator
Published on: December 15, 2021
Er-doped fiber frequency comb with mHz relative linewidth
Yunseok Kim1, Seungman Kim, Young-Jin Kim
1Ultrafast Optics for Ultraprecision Group, Korea Advanced Institute of Science and Technology, Science Town, Daejeon 305-701, Republic of Korea
Abstract:
A low-noise fiber frequency comb is demonstrated to improve the frequency accuracy and linewidth by suppressing the phase noise caused by the nonlinear self-phase modulation as well as the amplified spontaneous emission within the Er-doped fiber amplifier. The linewidth of the carrier-envelop- offset signal measures less than 1.9 mHz and the frequency stability well follows the reference Rb clock. This achievement will facilitate the use of the fiber frequency comb for industrial applications to precision near-infrared spectroscopy, frequency calibration, optical clocks and length metrology.
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