Negative index metamaterials based on metal-dielectric nanocomposites for imaging applications

Negative index metamaterials based on metal-dielectric nanocomposites for imaging applications

Negative index metamaterials are demonstrated based on metal-dielectric nanocomposites prepared using a versatile bottom-up nanofabrication approach. The method involves the incorporation of vertically aligned metal nanowires such as Au and Ag inside dielectric aluminum oxide nanotemplates. Optical absorbance measurements show resonance peaks corresponding to the transverse and longitudinal sur...

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

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 verifi...

Demonstration of metal–dielectric negative-index metamaterials with improved performance at optical frequencies

We experimentally demonstrate a comparatively low-loss negative-index metamaterial with the magnitude of the real part of the index comparable with the imaginary part. Over 40% transmission is achieved in the negative-index region by structural adjustment of the impedance matching between the metamaterial and the air–substrate claddings. This structure has the potential of achieving high transm...

On the dielectric function tuning of random metal-dielectric nanocomposites for metamaterial applications.

The potential of random metal-dielectric nanocomposites as constituent elements of metamaterial structures is explored. Classical effective medium theories indicate that these composites can provide a tunable negative dielectric function with small absorption losses. However, the tuning potential of real random composites is significantly lower than the one predicted by classical theories, due ...

Optical negative-index metamaterials