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arXiv · 1505.06781

Tuning the Quantum Efficiency of Random Lasers - Intrinsic Stokes-Shift and Gain

Andreas Lubatsch·Regine Frank
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Abstract

We report the theoretical analysis for tuning the quantum efficiency of solid state random lasers. Vollhardt-Woelfle theory of photonic transport in disordered non-conserving and open random media, is coupled to lasing dynamics and solved positionally dependent. The interplay of non-linearity and homogeneous non-radiative frequency conversion by means of a Stokes-shift leads to a reduction of the quantum efficiency of the random laser. At the threshold a strong decrease of the spot-size in the stationary state is found due to the increase of non-radiative losses. The coherently emitted photon number per unit of modal surface is also strongly reduced. This result allows for the conclusion that Stokes-shifts are not sufficient to explain confined and extended mode regimes.

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Andreas Lubatsch, Regine Frank. 2015-10-24. Tuning the Quantum Efficiency of Random Lasers - Intrinsic Stokes-Shift and Gain. https://doi.org/10.1038/srep17000

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