Optical Nonlocalities and Additional Waves in Epsilon-Near-Zero Metamaterials

Abstract

We analyze the optical properties of plasmonic nanorod metamaterials in the epsilon-near-zero regime and show, both theoretically and experimentally, that the performance of these composites is strongly affected by nonlocal response of the effective permittivity tensor. We provide the evidence of interference between main and additional waves propagating in the room-temperature nanorod metamaterials and develop an analytical description of this phenomenon. Additional waves are present in the majority of low-loss epsilon-near-zero structures and should be explicitly considered when designing applications of epsilon-near-zero composites, as they represent a separate communication channel.

Ferrell–Berreman Modes in Plasmonic Epsilon-near-Zero Media

“…This enhanced absorption in ENZ media has been exploited for novel polarization control and filtering in thin films [6], as well the proposal to use ENZ absorption resonances to tune thermal blackbody radiation of a heated object to the band-gap of a photovoltaic cell [7]. An enhanced non-linear response based upon strong spatial dispersion of waves in ENZ media has been demonstrated, and proposed for all-optical switching [8,9].Here we show theoretically and experimentally that ENZ metamaterials support unique absorption resonances related to radiative bulk plasmon-polaritons of thin metal films. These radiative bright modes exhibit properties in stark contrast to conventional dark modes of thin-film media (surface plasmon polaritons).…”

“…This enhanced absorption in ENZ media has been exploited for novel polarization control and filtering in thin films [6], as well the proposal to use ENZ absorption resonances to tune thermal blackbody radiation of a heated object to the band-gap of a photovoltaic cell [7]. An enhanced non-linear response based upon strong spatial dispersion of waves in ENZ media has been demonstrated, and proposed for all-optical switching [8,9].…”

Zero phase delay in negative-refractive-index photonic crystal superlattices

“…Metal-based NIMs 3-11 have been actively studied because of their unusual physical properties and their potential for use in many technological applications [12][13][14][15][16][17][18][19][20][21][22] ; however, they usually have the disadvantage of demonstrating large optical losses in their metallic components. As an alternative to metal-based NIMs, dielectricbased photonic crystals (PhCs) have been investigated and shown to emulate the basic physical properties of NIMs [23][24][25][26][27] , while also having relatively small absorption losses at optical frequencies.…”

Ultrafast plasmonics using transparent conductive oxide hybrids in the epsilon-near-zero regime

“…ENZ materials are of interest for a range of applications including tailoring of directional emission and radiation phase patterns, [1][2][3] air-guiding of electromagnetic waves, [4] and electromagnetic tunnelling devices. [5][6][7] While a lot of effort is aimed at achieving an ENZ response using artificial metamaterial resonators, some naturally occurring materials also show a strong reduction of the permittivity below that of vacuum.…”