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Improved signal-to-noise ratio of 10 GHz microwave signals generated with a mode-filtered femtosecond laser frequency comb
Published
Author(s)
Scott A. Diddams, Matthew S. Kirchner, Tara M. Fortier, Danielle Braje, A. M. Weiner, Leo W. Hollberg
Abstract
We use a Fabry-Perot cavity to optically filter the output of a Ti:sapphire frequency comb to integer multiples of the original 1 GHz mode spacing. This effectively increases the pulse repetition rate which is useful for several applications. In the case of low-noise microwave signal generation, such filtering leads to improved linearity of the high-speed photodiodes that detect the mode-locked laser pulse train. The result is significantly improved signal-to- noise ratio at the 10 GHz harmonic with the potential for a shot- noise limited single sideband phase noise floor near -168 dBc/Hz.
Diddams, S.
, Kirchner, M.
, Fortier, T.
, Braje, D.
, Weiner, A.
and Hollberg, L.
(2009),
Improved signal-to-noise ratio of 10 GHz microwave signals generated with a mode-filtered femtosecond laser frequency comb, Optics Express, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=842543
(Accessed October 22, 2025)