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arXiv · 1309.2412

Experimental and theoretical investigation of statistical regimes in random laser emission

Emilio Ignesti·Federico Tommasi·Lorenzo Fini·Stefano Lepri·Vivekananthan Radhalakshmi·Diederik Wiersma·Stefano Cavalieri
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Abstract

We present a theoretical and experimental study aimed at characterizing statistical regimes in a random laser. Both the theoretical simulations and the experimental results show the possibility of three region of fluctuations increasing the pumping energy. An initial Gaussian regime is followed by a Lévy statistics and Gaussian statistic is recovered again for high pump pulse energy. These different statistical regimes are possible in a weakly diffusive active medium, while the region of Lévy statistics disappears when the medium is strongly diffusive presenting always a Gaussian regime with smooth emission spectrum. Experiments and theory agree in identification of the key parameters determining the statistical regimes of the random laser.

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Emilio Ignesti, Federico Tommasi, Lorenzo Fini, Stefano Lepri, Vivekananthan Radhalakshmi, Diederik Wiersma, Stefano Cavalieri. 2013-09-10. Experimental and theoretical investigation of statistical regimes in random laser emission. https://doi.org/10.1103/physreva.88.033820

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