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Related papers: Why is the refractive index cannot be negative

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Our calculation shows that negative refractive index (NRI), which was known to exist only in metamaterials in the past, can be found in Dirac semimetals (DSM). Electrons in DSM have zero effective mass and hence the system carries no…

Other Condensed Matter · Physics 2021-12-02 Chih-Yu Chen , Ming-Chien Hsu , C. D. Hu , Yeu Chung Lin

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…

Applied Physics · Physics 2019-08-06 Mohamed Zein Radwan , Graeme Dewar

We show that a gas of relativistic electrons is a left-handed material at low frequencies by computing the effective electric permittivity and effective magnetic permeability that appear in Maxwell's equations in terms of the responses…

Quantum Gases · Physics 2020-12-02 C. A. A. de Carvalho , D. M. Reis , D. Szilard

We introduce a class of metamaterials with uniformly balanced gain and loss associated with complex permittivity and permeability constants. The refractive index of such a balanced pseudo-passive metamaterial is real. An unbounded uniform…

Optics · Physics 2015-01-12 A. Basiri , I. Vitebskiy , T. Kottos

Which systems are ideal to obtain negative refraction with no absorption? Electromagnetically induced transparency (EIT) is a method to suppress absorption and make a material transparent to a field of a given frequency. Such a system has…

Optics · Physics 2012-10-31 R. M. Rajapakse , E. Kuznetsova , S. F. Yelin

Electromagnetic metamaterials are man-made structures that have novel properties such as a negative refraction index, not attainable in naturally occurring materials. Although negative index materials (NIMs) in microwave frequencies were…

Applied Physics · Physics 2018-07-04 Hsun Chi Chan , Shulin Sun , Guang-Yu Guo

This paper intends to realize negative refraction with absorption suppressed by the electromagneticly induced transparency(EIT) in a dense four-level atomic system. Without the two equal transition frequencies responding to the probe field,…

Quantum Physics · Physics 2026-05-08 Shun-Cai Zhao

Negative refraction is demonstrated in one-dimensional (1D) dielectric photonic crystals (PCs) at microwave frequencies. Focusing by plano-concave lens made of 1D PC due to negative refraction is also demonstrated. The frequency-dependent…

Other Condensed Matter · Physics 2009-11-11 P. Vodo , W. T. Lu , Y. Huang , S. Sridhar

This paper presents a algebraic analysis of electromagnetic chirality-induced negative refractive index in a four-level atomic medium. According to analyze mathematically its argument of the complex refractive index for one circular…

Quantum Physics · Physics 2024-02-16 Shun-Cai Zhao , Qi-Xuan Wu , Ai-Ling Gong

Refractive index enhancement is crucial in the field of lithography, imaging, optical communications, solar devices and many more. We present a review of advancements in the process of designing high refractive index metamaterials, starting…

Optics · Physics 2022-04-05 Leena Singh , Weili Zhang

Electromagnetic metamaterials, made from arrangements of subwavelength sized structures, can be used to manipulate radiation. Designing metamaterials that have a positive refractive index along one axis and a negative refractive index along…

Instrumentation and Detectors · Physics 2015-01-07 Imran Mohamed , Giampaolo Pisano , Ming Wah Ng

We demonstrated a 2D helical chiral metamaterial that exhibits broadband strong optical activity resulting nonresonant Drude-like response. The strong chirality leads to broadband negative refractive index with high figure of merit (>90)…

Mediums which do not support the propagation of plane waves with negative phase velocity (NPV) when viewed at rest can support NPV propagation when they are viewed in a reference frame which is uniformly translated at sufficiently high…

Optics · Physics 2007-05-23 Tom G. Mackay , Akhlesh Lakhtakia

In light refraction between two transparent media, Snell's law describes the relationship between the incident angle and refraction angle. The refractive index is usually determined from Snell's law using the minimum deviation angle through…

Optics · Physics 2022-01-11 Shosuke Sasaki

The use of negative index materials is highly efficient for tayloring the spectral dispersion properties of a quarter-wavelength Bragg mirror and for obtaining a resonant behavior of a multilayer Fabry-Perot cavity over a very large…

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 quest to manipulate light propagation in ways not possible with natural media has driven the development of artificially structured metamaterials. One of the most striking effects is negative refraction, where the light beam deflects…

Optics · Physics 2025-02-14 L. Ruks , K. E. Ballantine , J. Ruostekoski

Increasing the refractive index available for optical and nanophotonic systems opens new vistas for design: for applications ranging from broadband metalenses to ultrathin photovoltaics to high-quality-factor resonators, higher index…

Optics · Physics 2021-03-30 Hyungki Shim , Francesco Monticone , Owen D. Miller

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…

Mesoscale and Nanoscale Physics · Physics 2016-09-27 Gil-Ho Lee , Geon-Hyoung Park , Hu-Jong Lee

We report numerical experiments of optical wave propagation in composites of high refractive index dielectric rods at frequencies where their first electric and magnetic Mie resonances are excited. The arrays of these particles have been…

Optics · Physics 2015-06-03 F. J. Valdivia-Valero , M. Nieto-Vesperinas