  A metamaterial formed by superconducting circuits or quantum dots can serve
as active lasing medium when coupled to a microwave resonator. For these
artificial atoms, in contrast to real atoms, variations in their parameters
cannot be avoided. In this paper, we examine the influence of disorder on such
a multi-atom lasing setup. We find that the lasing process evolves into a
self-organized stationary state that is quite robust against disorder. The
reason is that photons created by those atoms which are in or close to
resonance with the resonator stimulate the emission also of more detuned atoms.
Not only the number of photons grows with the number of atoms, but also the
width of the resonance as function of the detuning. Similar properties are
found for other types of disorder such as variations in the individual
coupling. We present relations how the allowed disorder scales with the number
of atoms and confirm it by a numerical analysis. We also provide estimates for
the sample-to-sample variations to be expected for setups with moderate numbers
of atoms.
