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Single-branch Er:fiber frequency comb for precision optical metrology with 10-18 fractional instability



Holly F. Leopardi, Josue Davila-Rodriguez, Franklyn J. Quinlan, Judith B. Olson, Scott A. Diddams, Tara M. Fortier


Laser frequency combs based on erbium-doped fiber mode-locked lasers have shown great potential for compact, robust and efficient optical clock comparisons. However, to simultaneously compare multiple optical clock species, fiber laser frequency combs typically require multiple amplifiers and fiber optic paths that reduce the achievable frequency stability near 1 part in 1016 at 1s. In this paper we describe an erbium-fiber laser frequency comb that overcomes these conventional challenges and supports optical frequency synthesis at the millihertz level, or fractionally 3 × 10-18 -1/2 by ensuring that all critical fiber paths are within the servo- controlled feedback loop. We demonstrate the application of this frequency comb as a synthesizer for optical clocks operating across a wavelength range from 650 nm to 2100 nm.


atomic clocks, Er:fiber laser, optical cavity, optical comparisons, optical frequency combs, precision metrology, ultrafast optics


Leopardi, H. , Davila-Rodriguez, J. , Quinlan, F. , Olson, J. , Diddams, S. and Fortier, T. (2017), Single-branch Er:fiber frequency comb for precision optical metrology with 10<sup>-18</sup> fractional instability, Optica (Accessed April 12, 2024)
Created August 1, 2017, Updated March 26, 2018