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Related papers: Why is the refractive index cannot be negative

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A novel active negative index metamaterial that derives its gain from an electron beam is intro- duced. The metamaterial consists of a stack of equidistant parallel metal plates perforated by a periodic array of holes shaped as…

Optics · Physics 2013-05-30 M. A. Shapiro , S. Trendafilov , Y. Urzhumov , A. Alu , R. J. Temkin , G. Shvets

A metamaterial with a negative effective index of refraction is made from a three-dimensional hexagonal lattice photonic crystal with a metallic basis embedded in foam. It has been simulated with Ansoft HFSSTM in a frequency range from 7.0…

Optics · Physics 2007-07-01 Ali Mahmoudi , Abbas Semnani , Ramazan Alizadeh , Roohollah Adeli

Negative index of refraction has become an accepted part of transformation optics, which is encountered in transformations that change the orientation of the manifold. Based on this concept, various designs of perfect lenses have been…

Optics · Physics 2009-12-15 L. Bergamin

We present the blueprint for a novel negative-index metamaterial. This structure is fabricated via three-dimensional two-photon direct laser writing and silver shadow evaporation. The comparison of measured linear optical spectra with…

Negative refraction, which reverses many fundamental aspects of classical optics, can be obtained in systems with negative magnetic permeability and negative dielectric permittivity. This Letter documents an experimental realization of…

Strongly Correlated Electrons · Physics 2007-05-23 A. Pimenov , P. P. Przyslupski , B. Dabrowski , A. Loidl

We have analytically determined the refractive index for the mechanical refraction of a relativistic particle for its all possible speeds. We have critically analysed the importance of Descartes' metaphysical theory and extended it in this…

Classical Physics · Physics 2024-05-27 Bikram Keshari Behera , Surendra Kumar Gour , Shyamal Biswas

We present simulation results of a design for negative index materials that uses magnetic resonators to provide negative permeability and metal film for negative permittivity. We also discuss the possibility of using semicontinuous metal…

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…

Optics · Physics 2007-05-23 Z. G. Dong , S. N. Zhu , H. Liu , J. Zhu , W. Cao

The theoretical mechanism for realizing the negative refractive index with {\it electromagnetically induced transparency} (EIT) is studied. It is shown that in a three-level dense atomic gas, there is a frequency band in which the EIT…

Materials Science · Physics 2009-09-29 Jian Qi Shen , Zhi Chao Ruan , Sailing He

It is demonstrated that a structured material formed by nonconnected crossed metallic wires may enable negative refraction over a wide frequency range. This phenomenon is a consequence of the anomalous dispersion characteristics of the…

Materials Science · Physics 2015-05-13 M. G. Silveirinha

We demonstrate a metamaterial that cannot be described by a single set of refractive-index and impedance values, even for fixed frequency and polarization. The metamaterial structure is a stack of dissimilar waveguides with subwavelength…

Interfaces between media with negative relative refractive index generically support propagating electromagnetic surface polariton modes with large wavenumber. The relation of these modes to a recent prediction by Pendry of ``perfect (real)…

Condensed Matter · Physics 2007-05-23 F. D. M. Haldane

Manipulation of the refractive index has been of growing interest lately. We consider parameters and possibilities of enhancing the absolute-value limit of the linear index in coherent atomic systems. Starting with a review of how two-level…

Optics · Physics 2024-02-20 Robert A. McCutcheon , Susanne F. Yelin

We suggest a scheme for obtaining negative refraction with low absorption in a left-handed atomic system.Under the the appropriate conditions,the atomic system displays negative refraction with negative permittivity and…

Quantum Physics · Physics 2026-05-12 Shun-Cai Zhao , Zheng-Dong Liu , Gen Li , Nian Liu

There are three widely-used conditions for characterizing negative refraction in isotropic dielectric-magnetic materials. Here we demonstrate that whilst all the different conditions are equivalent for purely passive media, they are…

Optics · Physics 2014-09-12 P. Kinsler , M. W. McCall

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…

Classical Physics · Physics 2007-05-23 Yu. P. Bliokh , J. Felsteiner

We show that negative refraction in materials can occur at frequencies $\omega$ where the real parts of the permittivity $\veps(\omega)$ and the permeability $\mu(\omega)$ have different sign, and that light with such frequencies can…

Optics · Physics 2024-06-24 Y. B. Band , Igor Kuzmenko , Marek Trippenbach

A uniaxial chiral metamaterial is constructed by double-layered four "U" split ring resonators mutually twisted by 90 degrees. It shows a giant optical activity and circular dichroism. The retrieval results reveal that a negative refractive…

It is found that the amphoteric refraction, i.e. the refraction can be either positive or negative depending on the incident angles, could occur at a planar interface associated with a uniaxially anisotropic positive index media (PIM) or an…

Optics · Physics 2007-05-23 Hailu Luo , Wei Hu , Xunong Yi , Haiying Liu , Jing Zhu

Negative refraction through a triangular prism may be explained without assigning a negative refractive index to the prism by using array theory. For the case of a beam incident upon the wedge, the array theory accurately predicts the beam…

Optics · Physics 2018-03-14 Gregory A. Talalai , Timothy J. Garner , Steven J. Weiss
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