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Pulse delay time statistics in a superradiant laser with calcium atoms

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 نشر من قبل Andreas Hemmerich
 تاريخ النشر 2019
  مجال البحث فيزياء
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Cold samples of calcium atoms are prepared in the metastable $^{3}$P$_{1}$ state inside an optical cavity resonant with the narrow band (375 Hz) $^{1}$S$_{0} rightarrow ^{3}$P$_{1}$ intercombination line at 657 nm. We observe superradiant emission of hyperbolic secant shaped pulses into the cavity with an intensity proportional to the square of the atom number, a duration much shorter than the natural lifetime of the $^{3}$P$_{1}$ state, and a delay time fluctuating from shot to shot in excellent agreement with theoretical predictions. Our incoherent pumping scheme to produce inversion on the $^{1}$S$_{0} rightarrow ^{3}$P$_{1}$ transition should be extendable to allow for continuous wave laser operation.



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