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arXiv · 1701.03157

A compact, thermal noise limited reference cavity for ultra-low noise microwave generation

J. Davila-Rodriguez·F. N. Baynes·A. D. Ludlow·T. M. Fortier·H. Leopardi·S. A. Diddams·F. Quinlan
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Abstract

We demonstrate an easy to manufacture, 25 mm long ultra-stable optical reference cavity for transportable photonic microwave generation systems. Employing a rigid holding geometry that is first-order insensitive to the squeezing force and a cavity geometry that improves the thermal noise limit at room temperature, we observe a laser phase noise that is nearly thermal noise limited for three frequency decades (1 Hz to 1 kHz offset) and supports 10 GHz generation with phase noise near -100 dBc/Hz at 1 Hz offset and <-173 dBc/Hz for all offsets >600 Hz. The fractional frequency stability reaches $2\times10^{-15}$ at 0.1 s of averaging.

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J. Davila-Rodriguez, F. N. Baynes, A. D. Ludlow, T. M. Fortier, H. Leopardi, S. A. Diddams, F. Quinlan. 2017-01-06. A compact, thermal noise limited reference cavity for ultra-low noise microwave generation. https://doi.org/10.1364/ol.42.001277

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