Optical negative-index bulk metamaterials consisting of 2D perforated metal-dielectric stacks

Abstract

Numerical simulations of a near-infrared negative-index metamaterial (NIM) slab consisting of multiple layers of perforated metal-dielectric stacks exhibiting a small imaginary part of the index over the wavelength range for negative refraction are presented. A consistent effective index is obtained using both scattering matrix and modal analysis approaches. Backward phase propagation is verified by calculation of fields inside the metamaterial. The NIM figure of merit, [ -Re(n)/Im(n) ], for these structures is improved by ~ 10x compared with previous reports, establishing a new approach to thick, low-loss metamaterials at infrared and optical frequencies.

Hybridization effect in coupled metamaterials

“…The improved transmission property can be realized at a certain range of metal layer thickness as shown in Figure 10 (c), indicating a reduced loss in such a coupled system. This result in a certain extent explained the former results [84], and was later proved by our experimental result. Moreover, this coupling mechanism provides an encourage vision to realizing a real 3-D negative index metamaterial, which is ultimately fulfilled by X.…”

“…It was numerically shown that the optical transmission loss for this negative refraction mode can even lower down by stacking more fishnet elements in the propagation direction [84]. However, the underlying physics remains obscure.…”

Past achievements and future challenges in the development of three-dimensional photonic metamaterials

“…The obvious next step 30 is to stack an integer number N>1 of functional layers of the double-fishnet (2N+1 actual layers) to eventually achieve a bulk 3D uniaxial negativeindex metamaterials (see Fig. 2(a)).…”

Broadband negative refraction in stacked fishnet metamaterial

“…Among various types of NIMs, one most promising candidate is the so-called fishnet NIM which comprises of alternating metal/dielectric layers perforated with two-dimensional array of holes [11][12][13][14][15] . The simple structure also provides a feasible solution for optical NIM [16][17][18][19][20][21] .…”

“…In the previous studies on the fishnet NIMs [11][12][13][14][15][16][17][18][19][20][21] , the light waves are incident on the top interface of the metal/dielectric multi-layers. Below the cut-off frequency of air holes the light waves can not penetrate into the structure and the negative index was retrieved within in a narrow frequency range above the cut-off.…”