Designed surface modes propagating along hyperbolic metamaterials

We report on surface-wave propagation (SWP) that occurs in semi-infinite hyperbolic metamaterials whose optical axis is set in the interface plane. In practice it is implemented by a multi-layered metal-dielectric nanostructure that is cut normally to the layers. Our theoretical analysis shows that various conditions can be designed enabling distinct regimes of SWP. We concluded that hybridization of SWP polarization leads to tighter confinement near the interface as compared with conventional surface plasmon polaritons. By using the finite-element method (FEM), we demonstrate that the fields are enhanced on the walls of metallic films, and thus minimizing significantly its presence inside the metal. This leads to the reduction of dissipation in the lossy metamaterial and allow for the existence of long-range surface waves that propagate obliquely to the optical axis. This suggests applications in nanosensing and nanoimaging.