Decay rate distributions of disordered slabs and application to random lasers

We compute the distribution of the decay rates (also referred to as residues) of the eigenstates of a disordered slab from a numerical model. From the results of the numerical simulations, we are able to find simple analytical formulas which describe these results well. This is possible for samples both in the diffusive and in the localized regimes. As an example of a possible application, we investigate the lasing threshold of random lasers.