Design of a Hyperbolic Metamaterial as a Waveguide for Low-Loss Propagation of Plasmonic Wave

Precise topological transition and negative refraction of a wave vector in a symmetrically arranged Al2O3/Ag/Al2O3 multilayer

The topological transition of a symmetrically arranged Al₂O₃/Ag/Al₂O₃ multilayer is precisely estimated by the product of characteristic film matrixes instead of treating the multilayer as an anisotropic medium with effective medium approximation. The variation of the iso-frequency curve among a type I hyperbolic metamaterial, a type II hyperbolic metamaterial, a dielectric-like medium, and a metal-like medium of such a multilayer with wavelength and the filling fraction of the metal is investigated. The estimated negative refraction of wave vector in a type II hyperbolic metamaterial is demonstrated with near field simulation.

High-performance photonic spin Hall effect in anisotropic epsilon-near-zero metamaterials

A high-performance photonic spin Hall effect is demonstrated in an anisotropic epsilon-near-zero (ENZ) metamaterial based on the wave-vector-varying Pancharatnam-Berry phase. The giant out-of-plane anisotropy of ENZ metamaterial induces strong spin-orbit coupling. With a small incident angle, photons with opposite spins move along opposite transverse directions gradually. After transmitting through a submicrometer thick ENZ metamaterial, the spin photons are fully separated with a spin separation of 2.7 times beam waist and transmittance of 70.1%, allowing a figure of merit F up to 1.9. A practical ENZ metamaterial consisting of an Ag nanorod array is proposed, whose figure of merit is still up to 0.006. This high-performance photonic spin Hall effect provides an integrated and practical way for the development of spin-photonic devices.