Self-optimization of optical confinement in ultraviolet photonic crystal   slab laser
  We studied numerically and experimentally the effects of structural disorder on the performance of ultraviolet photonic crystal slab lasers. Optical gain selectively amplifies the high-quality modes of the passive system. For these modes, the in-plane and out-of-plane leakage rates may be automatically balanced in the presence of disorder. The spontaneous optimization of in-plane and out-of-plane confinement of light in a photonic crystal slab may lead to a reduction of the lasing threshold. 
Alexey Yamilov, X. Wu, X. Liu, R. P. H. Chang, and H. Cao