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arXiv · 1808.08169

Optoelectronic nibbling of laser linewidth using a Brillouin-assisted optical phase-locked loop

Gwennael Danion·Marc Vallet·Ludovic Frein·Pascal Szriftgiser·Mehdi Alouini
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Abstract

We demonstrate that the implementation of phase-locked loop forbidding multimode operation of a long Brillouin resonator also leads to a dramatic reduction of the optical phase noise of the pump itself. In the case of a continuous Er,Yb:glass laser, a reduction by more than 90 dB at 100 Hz of the carrier is observed. This yields an optical linewidth estimated narrower than 2 Hz for the pump laser. The method being independent of the laser wavelength, it can be applied to almost any laser.

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Gwennael Danion, Marc Vallet, Ludovic Frein, Pascal Szriftgiser, Mehdi Alouini. 2018-08-24. Optoelectronic nibbling of laser linewidth using a Brillouin-assisted optical phase-locked loop. https://arxiv.org/abs/1808.08169

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