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This paper studies the near field refraction problem with loss of energy in negative refractive index material. Based on the relative refractive index $\kappa$, the analysis is categorized into two cases, namely $\kappa < -1$ and $-1 <…

Analysis of PDEs · Mathematics 2026-03-12 Feida Jiang , Haokun Sui

The far field refractor problem with a discrete target is solved with a numerical scheme that uses and simplify ideas from Caffarelli, Kochengin and Oliker. A numerical implementation is carried out and examples are shown.

Numerical Analysis · Mathematics 2016-03-07 Roberto De Leo , Cristian E. Gutiérrez , Henok Mawi

We consider the inverse refractor and the inverse reflector problem. The task is to design a free-form lens or a free-form mirror that, when illuminated by a point light source, produces a given illumination pattern on a target. Both…

Optics · Physics 2015-12-08 Kolja Brix , Yasemin Hafizogullari , Andreas Platen

An array of pairs of parallel gold nanorods is shown to have a negative refractive index n'=-0.3 at the optical communication wavelength of 1.5 micron. This effect results from the plasmon resonance in the pairs of nanorods for both the…

In this paper, we show that the near field reflector problem is a nonlinear optimization problem. From the corresponding functional and constraint function, we derive the Monge-Amp\`ere type equation for such a problem.

Analysis of PDEs · Mathematics 2012-03-13 Jiakun Liu

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…

We consider the problem of radiative transfer in stellar atmospheres where the index of refraction departs from unity and is a function of density and temperature. We present modified Feautrier and Lambda-iteration methods to solve the…

Astrophysics · Physics 2009-11-10 P. M. Kowalski , D. Saumon

We present an abstract method in the setting of compact metric spaces which is applied to solve a number of problems in geometric optics. In particular, we solve the one source near field refraction problem. That is, we construct surfaces…

Analysis of PDEs · Mathematics 2015-06-16 Cristian E. Gutierrez , Qingbo Huang

This research focuses on a coherently driven four-level atomic medium with the aim of inducing a negative index of refraction while taking into consideration local field corrections as well as magnetoelectric cross coupling, i.e. chirality,…

Materials Science · Physics 2011-07-06 F. Bello

We present two uniqueness results for the inverse problem of determining an index of refraction by the corresponding acoustic far-field measurement encoded into the scattering amplitude. The first one is a local uniqueness in determining a…

Analysis of PDEs · Mathematics 2013-08-28 Guanghui Hu , Hongyu Liu

We study the problem of constructing an optical surface separating two homogeneous, isotropic media, one of which has a negative refractive index. In doing so, we develop a vector form of Snell's law, which is used to study surfaces…

Optics · Physics 2023-07-19 Cristian E. Gutierrez , Eric Stachura

The inverse reflector problem arises in geometrical nonimaging optics: Given a light source and a target, the question is how to design a reflecting free-form surface such that a desired light density distribution is generated on the…

Numerical Analysis · Mathematics 2015-03-27 Kolja Brix , Yasemin Hafizogullari , Andreas Platen

Refractive index is a fundamental optical property of powder and a key input to the measurement of the size distribution using light scattering and the measurement of the absorption and scattering coefficients using diffuse reflectance…

Optics · Physics 2024-03-05 Cory Juntunen , Adam J. Rish , Carl Anderson , Yongjin Sung

A key optical parameter characterizing the existence of negative refraction in a thin layer of a composite material is the effective refractive index of an equivalent, homogenized layer with the same physical thickness as the initial…

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…

Optics · Physics 2014-06-03 Nian-Hai Shen , Thomas Koschny , Maria Kafesaki , Costas M. Soukoulis

The inverse reflector problem aims to design a freeform reflecting surface that can direct the light from a specified source to produce the desired illumination in the target area, which is significant in the field of geometrical…

Numerical Analysis · Mathematics 2025-03-28 Gang Bao , Yixuan Zhang

We propose a coherent optical method for creating negative refractive index (NRI) for a gaseous ensemble of ground-state polar molecules possessing both permanent electric and magnetic moments. Exploiting the pure rotational transition…

Two methods of refractometry in reflected light from optical surface of samples are considered and studied experimentally. Methods are grounded on results of Fresnel theory of concerning light reflectivity at near normal incidence and…

Optics · Physics 2010-08-26 E. A. Tikhonov , V. A. Ivashkin

We develop an approach to use nanostructured plasmonic materials as a non-magnetic negative-refractive index system at optical and near-infrared frequencies. In contrast to conventional negative refraction materials, our design does not…

Specially designed metal-dielectric composites can have a negative refractive index in the optical range. Specifically, it is shown that arrays of single and paired nanorods can provide such negative refraction. For pairs of metal rods, a…

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