Terahertz plasmonic random metamaterial

We explore the terahertz electromagnetic properties of a composite metamaterial consisting of subwavelength-sized dielectric particles with metallic inclusions. We observe group refractive index exhibits atypical which cannot be explained by conventional effective medium theory. It is shown to arise from near-field particle-plasmon coupling between the metallic particles. Moreover, we provide evidence of electron spin-dependent terahertz plasmonic transport through both ferromagnetic and ferromagnetic/nonmagnetic metamaterials.