相关论文: Negative Refraction Requires Strong Inhomogeneity

A negative-phase-velocity condition derived by Depine and Lakhtakia [Microwave Opt Technol Lett 41 (2004) 315] for isotropic, homogeneous, passive, dielectric-magnetic materials is inapplicable as a negative-refraction condition for active…

Wave refraction in negative-index media is always negative.

A robust wedge setup is proposed to unambiguously demonstrate negative refraction for negative index metamaterials. We applied our setup to several optical metamaterials from the literature and distinctly observed the phenomena of negative…

Well-established textbook arguments suggest that static electric susceptibility must be positive in "all bodies" [1]. However, it has been pointed out that media that are not in thermodynamic equilibrium are not necessarily subject to this…

We obtain convergent power series representations for Bloch waves in periodic high-contrast media. The material coefficient in the inclusions can be positive or negative. The small expansion parameter is the ratio of period cell width to…

Metasurface anomalous reflectors can enhance future wireless communication systems due to their ability to redirect electromagnetic waves and establish metasurface-assisted communication links. However, metasurface reflectors typically…

The static diffraction intensity distribution from large material system conceived as perfectly homogeneous system made inhomogeneous, though substitution of groups of atoms, small particles, by other groups of atoms, is explicitly…

We analyze different factors which influence the negative refraction in solids and multi-atom molecules. We find that this negative refraction is significantly influenced by simultaneous multi-electron transitions with the same transition…

Negative reflection and negative refraction are exotic phenomena that can be achieved by platforms such as double-negative metamaterial, hyperbolic metamaterial, and phase-discontinuity metasurface. Recently, natural biaxial van der Waals…

Photonic crystals and metamaterials are two overarching paradigms for manipulating light. Combining the two approaches leads to hypercrystals: hyperbolic dispersion metamaterials that undergo periodic modulation and mix…

In Phys. Rev. Lett. 91, 157404 (2003) Yong Zhang et al. study light propagation through an interface between two identical but differently oriented uniaxial crystals. The authors show that the light refraction at the interface at some…

Half a century ago, Veselago proposed left-handed materials with negative permittivity and permeability, in which waves propagate with phase and group velocities in opposite directions. Significant work has been undertaken to attain this…

We show why and when optics needs thickness as well as width or area. Wave diffraction explains the fundamental need for area or diameter of a lens or aperture to achieve some resolution or number of pixels in microscopes and cameras. Now…

We investigate theoretically and numerically the photonic band structure in the optical domain of an array of core-shell metal-semiconductor nanowires. Corresponding negative-index photonic bands are calculated, showing isotropic…

Recently it has been shown that due to losses the claims on observation of negative refraction using metamaterials are questionable. In this paper we discus an interesting case that is based in almost zero permeability at a given frequency:…

Unavoidable variations in size and position of the building blocks of photonic crystals cause light scattering and extinction of coherent beams. We present a new model for both 2 and 3-dimensional photonic crystals that relates the…

The size of micromagnetic structures, such as domain walls or vortices, is comparable to the exchange length of the ferromagnet. Both, the exchange length of the stray field $l_s$ and the magnetocrystalline exchange length $l_k$ are…

Photonic crystals with a sufficiently high refractive index contrast display partial or full band gaps. However, imperfections in the metamaterial cause light scattering and extinction of the interfering propagating waves. Positive as well…

We study the bandgap properties of two-dimensional photonic crystals created by a lattice of rods or holes conformed in a symmetric or asymmetric triangular structure. Using the plane-wave analysis, we calculate a minimum value of the…

Metasurfaces provide a compact, flexible, and reliable solution for controlling the wavefront of light. In imaging systems, micro-lens arrays are integrated with pixel matrices to reduce optical crosstalk, enhance photon collection…