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arXiv · 1208.0244

CaF2 Whispering-Gallery-Mode Resonator Stabilized Narrow Linewidth Laser

B. Sprenger·H. G. L. Schwefel·Z. H. Lu·S. Svitlov·L. J. Wang
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Abstract

A fiber laser is stabilized using a Calcium Fluoride (CaF2) whispering-gallery-mode resonator. It is set up using a semiconductor optical amplifier as a gain medium. The resonator is critically coupled through prisms, and used as a filtering element to suppress the laser linewidth. Using the self-heterodyne beat technique the linewidth is determined to be 13 kHz. This implies an enhancement factor of 10^3 with respect to the passive cavity linewidth. The three-cornered hat method shows a stability of 10^(-11) after 10 μs.

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B. Sprenger, H. G. L. Schwefel, Z. H. Lu, S. Svitlov, L. J. Wang. 2012-08-01. CaF2 Whispering-Gallery-Mode Resonator Stabilized Narrow Linewidth Laser. https://doi.org/10.1364/ol.35.002870

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