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Microresonator frequency comb optical clock



Scott B. Papp, Katja M. Beha, Pascal P. Del'Haye, Franklyn J. Quinlan, Hansuek Lee, Kerry J. Vahala, Scott A. Diddams


Optical frequency combs enable measurement precision at the 20th digit, and measurement accuracy entirely commensurate with their reference oscillator. A new direction in experiments is the creation of ultracompact frequency combs by way of nonlinear parametric optics in microresonators. We refer to these as microcombs, and here we report a silicon-chip-based microcomb optical clock that is stable and accurate. A low-noise microcomb spectrum with 33 GHz mode spacing and 25 THz span is generated with a 2 mm silica disk. This spectrum is stabilized to rubidium transitions separated by 3.5 THz by controlling two teeth 108 apart. The optical clock's output is the electronically countable ~33 GHz microcomb line spacing, which features an absolute stability better than the rubidium transitions by the expected factor of 108. Our work demonstrates the comprehensive set of tools needed for interfacing microcombs to state-of-the-art optical clocks.


four-wave mixing, microcavity devices, nonlinear optics, parametric processes


Papp, S. , Beha, K. , Del'Haye, P. , Quinlan, F. , Lee, H. , Vahala, K. and Diddams, S. (2014), Microresonator frequency comb optical clock, Optica, [online], (Accessed July 19, 2024)


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Created July 1, 2014, Updated February 19, 2017