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arXiv · 1903.10196

Pulse delay time statistics in a superradiant laser with calcium atoms

Torben Laske·Hannes Winter·Andreas Hemmerich
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Abstract

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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Torben Laske, Hannes Winter, Andreas Hemmerich. 2019-03-25. Pulse delay time statistics in a superradiant laser with calcium atoms. https://doi.org/10.1103/physrevlett.123.103601

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