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arXiv · 1703.05983

Phase noise characterization of sub-hertz linewidth lasers via digital cross correlation

Xiaopeng Xie·Romain Bouchand·Daniele Nicolodi·Michel Lours·Christophe Alexandre·Yann Le Coq
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Abstract

Phase noise or frequency noise is a key metrics to evaluate the short term stability of a laser. This property is of a great interest for the applications but delicate to characterize, especially for narrow line-width lasers. In this letter, we demonstrate a digital cross correlation scheme to characterize the absolute phase noise of sub-hertz line-width lasers. Three 1,542 nm ultra-stable lasers are used in this approach. For each measurement two lasers act as references to characterize a third one. Phase noise power spectral density from 0.5 Hz to 0.8 MHz Fourier frequencies can be derived for each laser by a mere change in the configuration of the lasers. This is the first time showing the phase noise of sub-hertz line-width lasers with no reference limitation. We also present an analysis of the laser phase noise performance.

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Xiaopeng Xie, Romain Bouchand, Daniele Nicolodi, Michel Lours, Christophe Alexandre, Yann Le Coq. 2017-03-17. Phase noise characterization of sub-hertz linewidth lasers via digital cross correlation. https://doi.org/10.1364/ol.42.001217

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