CaF2 whispering-gallery-mode-resonator stabilized-narrow-linewidth laser.
A fiber laser is stabilized by introducing a calcium fluoride (CaF(2)) whispering-gallery-mode resonator as a filtering element in a ring cavity. 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. A three-cornered-hat method is used and shows a stability of 10(-11) after 10 micros. 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.
Sprenger
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Max-Planck-Institute for the Science of Light, Günther-Scharowsky-Strasse 1, Bau 24, 91058 Erlangen, Germany.
Schwefel
H G L
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Lu
Z H
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Svitlov
S
S
Wang
L J
LJ