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arXiv · 0812.0266

Threshold of a Random Laser with Cold Atoms

Luis S. Froufe-Pérez·William Guerin·Rémi Carminati·Robin Kaiser
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Abstract

We address the problem of achieving an optical random laser with a cloud of cold atoms, in which gain and scattering are provided by the same atoms. The lasing threshold can be defined using the on-resonance optical thickness b0 as a single critical parameter. We predict the threshold quantitatively, as well as power and frequency of the emitted light, using two different light transport models and the atomic polarizability of a strongly-pumped two-level atom. We find a critical b0 on the order of 300, which is within reach of state-of-the-art cold-atom experiments. Interestingly, we find that random lasing can already occur in a regime of relatively low scattering.

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Luis S. Froufe-Pérez, William Guerin, Rémi Carminati, Robin Kaiser. 2008-12-01. Threshold of a Random Laser with Cold Atoms. https://doi.org/10.1103/physrevlett.102.173903

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