In this letter, we present a somewhat surprising result that very strong optical activity may be seen in a metamaterial system consisting of metamolecules that itself are not chiral. Negative refractive index metasurfaces for enhanced. Note a rather high transmittance of 25% and relatively low absorption of 10%. The negative refractive index in the optical range. Such behavior results from the plasmon resonance in the pairs of nanorods for both the electric and the magnetic components of light. Metamaterials and negative refraction cleo conference. Index terms left handed materials, metamaterials, nanoparticle plasmon resonance, negative refractive index. Negative refractive index metamaterials sciencedirect. Negative index of refraction in optical metamaterials purdue. Both experiments and simulations demonstrate that a negative refractive index n0. The complex index of refraction then becomes n vr e r m e i. Soukoulis1,3 1ames laboratory and department of physics and astronomy, iowa state university, ames, iowa 50011, usa 2institute of optical fiber commun. Jiangfeng zhou,1 thomas koschny,1,2 maria kafesaki,2 and costas m.
My question references materials with indices of refraction less than unity. Optical negative refraction in bulk metamaterials of nanowires. The index of refraction is a product of two complex functions. Both experiments and simulations demonstrate that a negative refractive index n approximately 0. Doctor of philosophy physics in the university of michigan. A slab of the negative refractive index metamaterial has a focal length that can be tuned by changing the gradient of the negative refractive index. An engineered material with simultaneous negative electric permittivity. Hence in a negative refractive index material, light makes a negative angle. Resolving the wave vector in negative refractive index media. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Special issue on metamaterials lhm microwave focusing and.
By representing the magnetic and electric response functions by lorentz oscillators in complex form we see that the index squared is n 2. Part of the contents of this chapter has been published in mrs bull. Materials that can achieve negative effective value of their refractive index were historically first termed left handed. Its worth taking a moment to describe the idea of negative refraction, which is the effect most associated with metamaterials.
Negative index of refraction in optical metamaterials osa. Soukoulis1,2, 1department of physics and astronomy and ames laboratory, iowa state university, ames, iowa 50011, usa. The refractive index is retrieved from direct phase and amplitude measurements for transmission and reflection, which are all in. Optical magnetism and negative refraction in plasmonic. Among the most soughtafter properties of metamaterials is the negative index of refraction. Nims are constructed of periodic basic parts called unit cells, which are usually significantly smaller than the wavelength of the externally applied electromagnetic. Index of refraction to control dispersive effects 381 mohammad mojahedi and george v. Aug 11, 2008 bulk optical metamaterials open up prospects for studies of 3d optical effects and applications associated with nims and zero index materials such as reversed doppler effect, superlenses, optical. Finally, it can be very difficult, and intellectually stimulating, to try and make the connection between what light is doing in an optical system and how the system would appear to a person looking at it. Pdf a doubleperiodic array of pairs of parallel gold nanorods is shown to have a negative refractive index in the optical range. This book deals with the subject of optical and electronic negative refraction nr and negative index materials nim.
Osa negative index of refraction in optical metamaterials. Negative index metamaterial or negative index material nim is a metamaterial whose refractive index for an electromagnetic wave has a negative value over some frequency range. Chapter 1 negative refractive index metamaterials in optics. For example, to xrays most solid materials are optically less dense than a vacuum and have a refractive index slightly less. Complementary chiral metamaterials with giant optical. Such an effect can be obtained using a metamaterial which has been designed to achieve a negative value for both electric permittivity. Negative refractive index due to chirality jiangfeng zhou,1 jianfeng dong,2,1 bingnan wang,1 thomas koschny,1,3 maria kafesaki,3 and costas m. A doubleperiodic array of pairs of parallel gold nanorods is shown to have a negative refractive index in the optical range. Ii smolyaninov, yj hung, and cc davis, pdfphysics 0610230. The imagi nary part of the refractive index also shows resonant behavior and it is large near the resonance. Can achieve negative index of refraction, zero index of refraction, magnetism at optical frequencies, etc. Shalaev, wenshan cai, uday chettiar, hsiaokuan yuan, andrey k. Negative effective refractive index metamaterials at optical frequencies based on superlattices of noble metals and excitonic semiconductors andrea vallecchi and matteo albani department of information engineering, university of siena, via roma 56, siena, 53100 italy. How can a dielectric material display a negative refractive index.
Osa metamaterials with gradient negative index of refraction. Optical negative index metamaterials by xuhuai zhang. Optical negativeindex metamaterials purdue university. Negative refractive index metamaterials supporting 2d waves. Published 30 january 20 20 iop publishing ltd journal of optics, volume 15, number 2. Negative refractive index in artificial metamaterials arxiv. Department of physics, the university of texas at austin, austin, tx 78712, united states received 31 july 2007. Soukoulis1,2 1ames laboratory and department of physics and astronomy,iowa state university, ames, iowa 50011. All successful designs for negative refractive index in the optical range have so far used the idea of creating a negative magnetic permeability by means of the excitation of asymmetric currents. Diverse approaches for achieving nr and nim are covered, such as using photonic c.
This effect results from the plasmon resonance in the pairs of nanorods for both the electric and magnetic components of light. Optical negativeindex metamaterials nature photonics. The first metamaterials with a negative index of refraction at optical frequencies have been demonstrated using pairs of metallic nanorods by shalaev, cai, chettiar, yuan, sarychev, drachev and kildishev 2005 shown schematically in fig. An array of pairs of parallel gold nanorods is shown to have a negative refractive index n0. Negative index of refraction in optical metamaterials vladimir m.
I believe the speed which can be calculated using this index is the phase velocity of light which does not carry information and can exceed c. A thin metal film pierced with holes of appropriate size or spacing between them can be used as a metamaterial with the gradient negative index of refraction. Negative index of refraction in optical metamaterials. Optical magnetism and negative refraction in plasmonic metamaterials yaroslav a. Kildishev school of electrical and computer engineering, purdue university, west lafayette, in 47907 an array of pairs of parallel gold nanorods is shown to have a negative refractive index. Below we focus on the recent progress in scaling magnetism and negative refraction up to the optical frequencies, and discuss some of the unusual properties of optical metamaterials. Negative refractive index metamaterials ucsd university of. The first demonstrations of negative refractive index metamaterials nims were at microwave frequencies, but a wide range of applications, for. Electromagnetic metamaterials intended for ultraviolet, visible or infrared range are termed optical metamaterials. For normal incidence, the light intensity only decays 0. Negative refractive index in chiral metamaterials shuang zhang,1 yongshik park,1 jensen li,1 xinchao lu,2 weili zhang,2 and xiang zhang1,3, 1nanoscale science and engineering center, university of california, 5 etcheverry hall, berkeley, california 947201740, usa. Pdf negative index of refraction in optical metamaterials. The refractive index is retrieved from direct phase and amplitude measurements for transmission and reflection, which are all in excellent agreement with simulations.
The proof of the existence of negative index of refraction was established using a snells law experiment with a wedge. Threedimensional 3d optical metamaterials have come into focus recently, including the realization of negative refraction by using layered semiconductor metamaterials and a 3d magnetic metamaterial in the infrared frequencies. It offers unprecedented control of both linear and nonlinear optical functions for applications ranging from optical switching, to negative and nearzero refractive index metamaterials, to chiral. Negative refraction is the name for an electromagnetic phenomenon where light rays are refracted at an interface in the reverse sense to that normally expected. Threedimensional optical metamaterial with a negative refractive index article pdf available in nature 4557211. Zhaofeng li 1,2, mehmet mutlu 1,2 and ekmel ozbay 1,2,3.
Emmms exhibit exotic properties not easily achieved using naturally occurring materials. Negative refractive index response of weakly and strongly coupled optical metamaterials. Lossfree and active optical negativeindex metamaterials. Ii smolyaninov, yj hung, and cc davis, pdfphysics0610230. Much research activity is being devoted to the design and fabrication of metamaterials, artificially tailored composites with the counterintuitive optical property of a negative refraction index. Threedimensional optical metamaterial with a negative. Negative refraction and focusing anan fang,1 thomas koschny,1,2 and costas m. We discuss optical constants in artificial metamaterials showing negative magnetic permeability and electric permittivity and suggest a simple formula for the. In addition to a negative index ni of refraction, properties such as artificial magnetism2, negative permittivity, and negative permeability have. Pdf threedimensional optical metamaterial with a negative.
Negative index of refraction in optical metamaterials v. Negative refractive index response of weakly and strongly. Foremost among these properties is a negative index of refraction. Complementary chiral metamaterials with giant optical activity and negative refractive index zhaofeng li,1,a kamil boratay alici,1 evrim colak,1 and ekmel ozbay1,2 1department of physics, nanotechnology research center, bilkent university, bilkent, 06800 ankara.
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