Analysis of a hyperprism for exciting high- k modes and subdiffraction imaging

Abstract

We study the effect of resonances on the ability of prisms made of hyperbolic metamaterials in the canalization regime (such as wire array media) to couple evanescent high spatial frequencies (high-k modes) to low spatial frequencies that propagate in the far-field zone. Using simple analytical models, we calculate the far-field propagation from the hyperprism. The resonant nature of the metal wire segments within the prism yields a transmission function identical to that of a grating, but with periodicity proportional to the wavelength, making the hyperprism function like a nondispersive grating. Numerically compensating the effect of resonances allows the hyperprism to be used as a one-dimensional imaging device able to resolve feature sizes below the diffraction limit if the host medium has a low refractive index. Furthermore, the hyperprism enables coupling of propagating plane waves to a range of high-k modes that can be increased by increasing the angle of the prism. We quantify how this tunable, nondispersive excitation of high-k modes opens up possibilities for new experimental approaches for coupling to plasmonic systems and for increased axial resolution in total internal reflection imaging, in particular in the terahertz spectrum.

Mode-resolved directional enhancement of spontaneous emission inside/outside finite multilayer hyperbolic metamaterials

“…Hyperbolic Metamaterials (HMMs) hold promise to embody the boundless possibilities in light-matter interaction on nanoscale [1]. Artificial materials having hyperbolic dispersion have been designed for various applications such as nano focusing [2], sensing [3,4], wave front manipulation [5], sub diffraction imaging [6,7], emission enhancement of quantum emitters [8,9] and many more. HMMs have attracted a great attention for spontaneous emission enhancement due to the large photonic Local Density of States (LDOS) associated with their unique modes having large wave vector, so called highk modes [10,11].…”

Polaritonic cylinders as multifunctional metamaterials: Single scattering and effective medium description

“…anisotropic metamaterials showing hypebolic dispersion relation, own to the mixed positive and negative values of their effective permittivity or permeability tensor components. Such metamaterials, which are usually realized by properly alternating metallic and dielectric layers or by employing metallic rod systems, show great potential in imaging applications [8,9], as they can offer almost perfect imaging, even with magnification (they can transform evanescent waves to propagating), and in spontaneous emission enhancement [10,11] (as they can offer very high density of EM states). (c) Metamaterials with permittivity near zero (ENZ) [12][13][14]; such metamaterials, which can be realized by properly engineering electrical permittivity resonances (e.g.…”