Metamaterials and spatial dispersion effects
In this talk an overview of various manifestations of spatial dispersion effects (nonlocality) in metamaterials will be provided. Effect of spatial dispersion on the topological transition in metamaterials will be discussed. Our studies suggest that besides elliptic and hyperbolic dispersion regime there exists a mixed dispersion regime combining the features of the former two regimes. The properties of the mixed dispersion regime will be summarized. Furthermore, the phenomenon of spatial-dispersion-induced birefringence in metamaterials with cubic symmetry will be reported along with our recent experimental results confirming the presence of the effect in resonant metamaterials. Finally, manifestations of nonlocality in uniaxially polarizable media and in nonlinear metamaterials will be highlighted. The results that will be discussed in the talk confirm the presence of pronounced spatial dispersion effects in a wide class of metamaterials and prove that the use of nonlocal electromagnetic response provides a novel degree of freedom in metamaterial engineering.