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Statistical regimes of random laser fluctuations

Stefano Lepri·Stefano Cavalieri·Gian-Luca Oppo·Diederik S. Wiersma
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Abstract

Statistical fluctuations of the light emitted from amplifying random media are studied theoretically and numerically. The characteristic scales of the diffusive motion of light lead to Gaussian or power-law (Levy) distributed fluctuations depending on external control parameters. In the Levy regime, the output pulse is highly irregular leading to huge deviations from a mean--field description. Monte Carlo simulations of a simplified model which includes the population of the medium, demonstrate the two statistical regimes and provide a comparison with dynamical rate equations. Different statistics of the fluctuations helps to explain recent experimental observations reported in the literature.

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Stefano Lepri, Stefano Cavalieri, Gian-Luca Oppo, Diederik S. Wiersma. 2006-11-06. Statistical regimes of random laser fluctuations. https://doi.org/10.1103/physreva.75.063820

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