相关论文: Mid-Infrared waveguides and negative refraction wi…
We identify a route towards achieving a negative index of refraction at optical frequencies based on coupling between plasmonic waveguides that support backwards waves. We show how modal symmetry can be exploited in metal-dielectric…
A type of 3-dimensional optical negative-refractive-index metamaterials composed of all dielectric nanospheres is proposed and demonstrated theoretically. The metamaterials are constructeded by pairing together two kinds of dielectric…
In this article, it has been theoretically shown that broad angle negative refraction is possible with asymmetric anisotropic metamaterials constructed by only dielectrics or loss less semiconductors at the telecommunication and relative…
We have made measurements of microwave transmission over the 12 - 18 GHz range and through a simple metamaterial exhibiting a negative index of refraction. The metamaterial consisted of an array of wires cladded in dielectric embedded in a…
We present the vertically illuminated Si compatible mid-infrared photodetectors based on graphene that forms negative-index metamaterial. The coupling into a 2D layer at the angles near normal to the surface is negligible without the help…
We propose deep-subwavelength optical waveguides based on metal-dielectric multilayer indefinite metamaterials with ultrahigh effective refractive indices. Waveguide modes with different mode orders are systematically analyzed with…
Negative refraction is known to occur in materials that simultaneously possess a negative electric permittivity and magnetic permeability; hence they are termed negative index materials. However, there are no known natural materials that…
A wedge-shaped structure made of split-ring resonators (SRR) and wires is numerically simulated to evaluate its refraction behavior. Four frequency bands, namely, the stop band, left-handed band, ultralow-index band, and positive-index…
We propose a leaky optical waveguide achieved with a uniaxially anisotropic metamaterial that supports both forward and backward leaky waves. The backward leaky nature is exploited in a sub-diffraction imaging system.
The propagation characteristics of magneto-quasistatic waves, more commonly, known as magnetostatic waves in a long, metallic rectangular waveguide filled with a metamaterial slab are comprehensively investigated. The metamaterial slab…
Negative refraction of acoustic waves is demonstrated through underwater experiments conducted at ultrasonic frequencies on a 3D locally resonant acoustic metafluid made of soft porous silicone-rubber micro-beads suspended in a yield-stress…
Due to the deep sub-wavelength unit cell in metamaterials, the quasi-static approximation is usually employed to describe the propagation. By making pairs of resonators, we highlight that multiple scattering also occurs at this scale and…
Two types of optical metamaterials operating at near-IR and mid-IR frequencies, respectively, have been designed, fabricated by nanoimprint lithography (NIL), and characterized by laser spectroscopic ellipsometry. The structure for the…
In this paper we consider a two-dimensional metamaterial comprising an array of qubits (two level quantum objects). Here we show that a two-dimensional quantum metamaterial may be controlled, e.g. via the application of a magnetic flux, so…
We demonstrate negative refraction of microwaves in metallic photonic crystals. The spectral response of the photonic crystal, which manifests both positive and negative refraction, is in complete agreement with band-structure calculations…
Noble metals such as gold and silver are the primary metallic building blocks of metamaterial devices. Making subwavelength-sized structural elements from these metals seriously limits the optical performance of a device, however, and…
Materials showing electromagnetic properties that are not attainable in naturally occurring media, the so called metamaterials, have been lately, and still are, among the most active fields in optical and materials physics and engineering.…
We leverage quantum graph theory to quickly and accurately characterise acoustic metamaterials comprising networks of interconnected pipes. Anisotropic bond lengths are incorporated in the model that correspond to space-coiled acoustic…
Negative refraction is such a prominent electromagnetic phenomenon that most researchers believe it can only occur in artificially engineered metamaterials. In this article, we report negative refraction for all incident angles for the…
Metal-based negative refractive index materials have been extensively studied in the microwave region. However, negative-index metamaterials have not been realized at near-IR or visible fre-quencies due to difficulties of fabrication and to…