The study of spatial dispersion of two-dimensional complex crystals, with periodic modulations of both gain-loss and the refractive index, reveals simultaneous nondiffractive-nondiffusive light propagation. Narrow light beams and light patterns propagate without dispersion while amplified through the complex material. We determine and explore nondiffractive-nondiffusive regimes for collinear and noncollinear propagation.
Herrero, R.; Botey, M.; Staliunas, K. Nondiffractive-nondiffusive beams in complex crystals. "Physical review A", 16 Juny 2014, vol. 89, núm. 6.