Transformation optics

About: Transformation optics is a research topic. Over the lifetime, 2687 publications have been published within this topic receiving 102378 citations.

Backward wave radiation from negative permittivity waveguides and its use for THz subwavelength imaging.

Abstract: In this paper we demonstrate the possibility of backward radiation from a negative permittivity planar (slab) waveguide. Furthermore, we show that backward radiation can be used to achieve sub-wavelength imaging of a point source placed close to such a slab or to a periodic layered system of slabs. Finally, we demonstrate backward-radiation-based imaging in the case of realistic materials operating in the THz regime, such as polaritonic alkali-halide systems.

Transformation-optics-inspired anti-reflective coating design for gradient index lenses.

Abstract: Recent developments in transformation optics have led to burgeoning research on gradient index lenses for novel optical systems. Such lenses hold great potential for the advancement of complex optics for a wide range of applications. Despite the plethora of literature on gradient index lenses, previous works have not yet considered the application of anti-reflective coatings to these systems. Reducing system reflections is crucial to the development of this technology for highly sensitive optical applications. Here, we present effective anti-reflective-coating designs for gradient index lens systems. Conventional anti-reflective-design methodologies are leveraged in conjunction with transformation optics to develop coatings that significantly reduce reflections of a flat gradient index lens. Finally, the resulting gradient-index anti-reflective coatings are compared and contrasted with conventional homogeneous anti-reflective coatings.

Lossy gradient index metamaterial with sinusoidal periodicity of refractive index: case of constant impedance throughout the structure

Abstract: We used an exact analytical approach to investigate the electromagnetic wave propagation across an isotropic metamaterial composite with i. a sinusoidally periodic gradient of the real parts of the effective permittivity and permeability, ii. spatially uniform imaginary parts of the effective permittivity and permeability, and iii. spatially uniform impedance. The real part of the effective refractive index can be positive and negative along the direction of nonhomogeneity. A remarkably simple direct solution for the field distribution was obtained.

A literature survey of mathematical study of metamaterials

Abstract: Since the successful construction of the so-called double negative metamaterials in 2000, there has been a growing interest in studying metamaterials across many disciplinaries. In this paper, we present a survey of recent progress in metamaterials and its applications from the mathematical point of view. Due to the great amount of papers published in this area, here we mainly discuss those issues interested to us. Our main goal is to attract more mathematicians to study this fascinating subject.

Negative-index metamaterials from nanoapertures

Abstract: We introduce an approach towards the design of metamaterials where the dielectric and magnetic activity is caused by resonances in dielectric nanocavities embedded in metal. The simplest implementation of this concept is a rectangular nanoaperture in a thin metallic stripe. We show that the electromagnetic field of the resonance eigenmodes is primarily concentrated in the dielectric medium. Even modes affect the effective permittivity, whereas odd modes evoke dispersion in the effective permeability. The negative permittivity provided by the metallic stripes allows potentially for a negative effective index near the first magnetic resonance. Advantages and disadvantages of this structure compared to metamaterials where the resonant eigenmodes are mainly localized at metallic nanoparticles are discussed.