General method for modeling nonlinear waves in active metamaterial and gyrotropic layered structures

Application of active and bi-anisotropic metamaterials, based on “artificial molecules” with “active loads” [1, 2], with “negative phase” behaviour, opens new perspectives. Here we present the generalized method, for modeling active (gain) media. The general method is applicable for electromagnetic (EM) waves in the layered structures including nonlinear and active bi-anisotropic metamaterials, [1,2], and gyrotropic nonlinear layeres [3, 4] with parametric coupling/amplification [5-7]. We apply the general nonlinear evolution equations in layered media to the formation of nonlinear structures under parametric coupling [5-7] in gyrotropic structures and illustrate an influence of gain on the formation and propagation of bullets ((2+1) spatial-temporal solitons). A possibility of spatial gain/ compensation of losses in metamaterials [8, 9], is shown.