Finally we have numerically calculated the reflectivity and the. 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. A similar effect can be accomplished with metal strips in which the refractive index can reach. Negative refractive index how is negative refractive index. According to the frequency of the source, we have different behaviors. Negative index of refraction in optical metamaterials v. A freestanding, multilayered fishnet metamaterial is reported to experimentally exhibit a negative refractive index in the greenlight spectral range. A case study of three plasmonic geometries jennifer a.
As for transparent materials into which the light actually refracts, the index cannot be negative. But this negative index medium remained as an academic curiosity for almost thirty years, until pendry et al2,3 proposed the designs of artificial structured materials which would have effectively negative permeability and permittivity. The relation between the refractive index and the concentration depends on the. 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.
Refractive index project gutenberg selfpublishing ebooks. Energy and momentum in negative refractive index materials. Pendry proposed that we could have a negative epsilon by arranging the metal wires in a simple cubic lattice. Experimental and theoretical verification of focusing in a. Limitations on subdiffraction imaging with a negative. This is called dispersion and causes prisms and rainbows to divide white light into its constituent spectral colors. The refractive index is retrieved from direct phase and amplitude measurements for transmission and reflection, which are all in. These materials, referred to as lefthanded lhm or negative index materials, possess unique electromagnetic properties and promise novel optical devices, including a perfect lens. Introduction in the late 1960s, veselago proposed that materials with simultaneously negative permittivity and permeability are. This paper deals with the experimental observation of a negative permeability in the. Kremer 1abstractrecent demonstrations of negative refraction utilize threedimensional collections of.
Surveying this explosive growth, physics and applications of negative refractive index materials covers the fundamental physical principles and emerging engineering applications of structured electromagnetic metamaterials that yield a negative refraction as well as other unexpected physical properties. These artificial dielectrics metamaterials consist of loosely coupled unit cells comprised of thin wire strips and split ring resonators to synthesize negative permittivity and permeability, respectively 24. Momentum density, momentum flow, and transfer in media with negative material parameters. Subpicosecond optical switching with a negative index. Shaping 3d path of electromagnetic waves using gradient. Keywords double negative media, metamaterials, negative refaction,r backward waves, planar waveg. But this definition is not gonna answer your question.
Metamaterials and enabling microwave devices george v. Pdf a report negative refractive index materials soham. May 20, 2018 as your familiar with the definition of refractive index, it is the ratio of velocity of light in vacuum that velocity of light in the given medium. Perfectly matched layer behavior in negative refractive. Indeed, it is now established that negative refraction can occur in materials displaying anisotropy, such as calcite, and in two or threedimensionally structured materials such as photonic crystals 11. With their potential for spectacular applications, like superlensing and cloaking, metamaterials are a powerful class of nanostructured materials. Attention has been given to the fundamentals of negative index materials, the main design strategies and proposed applications which include subwavelength. In the past few years, new developments in structured electromagnetic materials have given rise to negative refractive index materials which have both negative. 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. Metamaterials with negative permeability and permittivity. 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. A broadband negative index metamaterial at optical.
The refractive index is retrieved from direct phase and amplitude measurements for transmission and reflection, which are all in excellent agreement with simulations. Shalaev birck nanotechnology center, purdue university, west lafayette, in 47907, usa on leave from dtu, research center com and nanophotonics, dk2800 kgs. Atwater,2 and albert polman1 1center for nanophotonics, fominstitute for atomic and molecular physics amolf. Recently, some interest has shifted towards the realization of materials that exhibit zero or nearzero refractive index. The quantitative measure of this bending was provided by willebrord snell in 1621 18. Negative refractive index in coaxial plasmon waveguides ren. Wave propagation in negative index metamaterial youtube. Optics express focused issue on metamaterials 11, pp. Composites with negative refractive index, thermal, self. All these applications rely on the metamaterials acting as a homogeneous material. Department of electrical and computer engineering, university of toronto, ontario, m5s 3g4, canada. Eleftheriades department of electrical and computer. It is fascinating reading for scientists, engineers, and graduatelevel students in physics, chemistry, materials science, photonics, and. Planar negative refractive index media using periodically.
Surveying this explosive growth, physics and applications of negative refractive index materials covers the. Eleftheriades, senior member, ieee abstract we present the design and implementation of a periodically loaded transmission line, which simultaneously exhibits negative refractive index nri and negative group delay and. Birck nanotechnology center, purdue university, west lafayette, in 47907, usa on leave from dtu, research center com and nanophotonics, dk2800 kgs. The concept of a negative index of refraction, originally proposed by veselago in the 1960s 1, suggested the possibility of materials in which the permittivity and permeability could be made simultaneously negative. Physics and applications of negative refractive index materials. Such properties include controlled electromagnetic, selfhealing, thermal management, and selfsensing properties that interact to create an innovative multifunctional material system. We investigate a negative index metamaterial with a phasesensitive nearfield microscope and measure the optical phase as a function of distance. The arrows indicate the di rection of the phase velocity. By optimizing the design we show that inhomogeneous electromagnetic resonators with almost uniform field intensity and up to twice the energy density of conventional. Periodically loaded transmission line with effective negative. Negative refractive index in coaxial plasmon waveguides. A periodic array of such resonators exhibits negative refractive indices at optical frequencies in multiple regions exceeding 200 nm in bandwidth. Limitations on subdiffraction imaging with a negative refractive index slab david r. Can a transparent material have a negative refractive index.
Antoniades, negative refractiveindex transmissionline metamaterials and enabling electromagnetic applications, 2004 ieee antennas and propagation society international symposium. The realization of a negative refractive index at such a high frequency range mainly originates from lowloss magnetic resonance and interactions between the neighboring functional layers. Soukoulis1,3 1ames laboratory and department of physics and astronomy, iowa state university, ames, iowa 50011, usa 2institute of optical fiber commun. Archived from the original pdf on february 22, 2012.
Are negative index materials achievable with surface plasmon waveguides. Negative index materials nims have a negative refractive index so that electromagnetic waves in such media propagate in a direction opposite to the. A flexible metamaterial with negative refractive index at visible wavelength. Negative refractive index metamaterials ucsd university of.
Refraction at media with negative refractive index. Cummer, senior member, ieee abstractthe perfectly matched layer pml absorbing boundary condition is shown to be analytically unstable for a. Threedimensional optical metamaterial with a negative. Atwater,2 and albert polman1 1center for nanophotonics, fominstitute for atomic and molecular physics amolf, science park 104, 1098 xg amsterdam, the netherlands 2california institute of technology, 1200 east california boulevard, pasadena, california. The refractive index of materials varies with the wavelength and frequency of light. Pdf design of resonators using materials with negative. Experimental and theoretical verification of focusing in a large, periodically loaded transmission line negative refractive index metamaterial ashwin k. Recently, artificially constructed metamaterials have become of considerable interest, because these materials can exhibit electromagnetic characteristics unlike those of any conventional materials. Physics and applications of negative refractive index materials 1st.
Periodically loaded transmission line with effective. Narrow transmission mode in onedimensional symmetric. In nature, the only times that you can get a negative index of refraction is with a reflective surface, ie a mirror. Metamaterials are artificially engineered structures that have properties, such as a negative refractive index 1,2,3,4, not attainable with naturally occurring materials. Negative refractive index in lefthanded materials david r. Since a metamaterial is a material which is having negative permittivity and permeability, it can be regarded as an artificial medium with negative index of refraction. These have permitted emerging applications, concepts and devices to be developed in the last few years. Th e refractive index is one of the most fundamental characteristics of light propagation in materials. Osa freestanding optical negativeindex metamaterials of.
Response times in the 110 ps range would be possible provided materials with faster recombination times are used as the substrate. Recently, metamaterials that display negative refractive index a property not found in any known naturally occurring material have drawn significant scientific interest, underscoring the remarkable potential of metamaterials to facilitate new developments in electromagnetism. The metalens material parameters are nonmagnetic, isotropic, and inhomogeneous, which can be realized by nonresonant graded metamaterials. Any material that exhibits the property of negative refractive index, a property not observed in naturally occurring materials, will have a variety of practical applications, such as beam steerers, modulators, bandpass filters, and lenses permitting subwavelength point source focusing. A negative refractive index, a property that does not exist in natural materials, can be produced in socalled metamaterials by combining two building blocks.
Negativeindex materials were first predicted theoretically by. Propagation of radiation in negative refractive media 477 3. Negative refractive index metamaterial structure using srr. Phase mismatchfree nonlinear propagation in optical zero index materials.
Causality and energy density in frequency dispersive media. Such materials are sometimes called double negative materials. Homogenization and effective macroscopic material parameters 473 2. As your familiar with the definition of refractive index, it is the ratio of velocity of light in vacuum that velocity of light in the given medium. Use of isofrequency curves to describe positive and negative refraction has been outlined in ref. Negative refraction occurs at interfaces between materials at which one has an ordinary positive phase velocity i. A doubleperiodic array of pairs of parallel gold nanorods is shown to have a negative refractive index in the optical range. Pdf negative refractive index materials researchgate. A change from a conventional refractive index to a negative value gives incorrect results for conventional calculations, because some properties and effects have been altered. Muhan choi, jongho choe, byungsoo kang, choongi choi. The existence of negative refractive materials can result in a change in electrodynamic calculations for the case of permeability. Nims are constructed of periodic basic parts called unit cells, which are usually significantly smaller than the wavelength of the externally applied electromagnetic radiation. In addition, the refractive index also provides a measure of the deflection of a beam of light as it crosses the interface between two materials having different values for their refractive indices.
Osa negative index of refraction in optical metamaterials. Experimental verification of a negative index of refraction. Negative refractive index in optics of metaldielectric. Negative effective refractive index the complex refractive index of a given medium is defined as the ratio between the speed of an electromagnetic wave through that medium and that in vacuum and can thus be written as n2. Negative refractive index metamaterials supporting 2d waves. Effective negative refractive index and negative group velocity omar f. Negative refractive index in artificial metamaterials. As the refractive index varies with wavelength, so will the refraction angle as light goes from one material to another.
This demonstration of a previously unexploited electromagnetic em property proved the importance of engineered materials and has resulted in an extraordinary amount of continued development by scientists working in optics. Concentration in most solutions, the concentration of solute in a solvent can be determined by measuring the refractive index n d. We have also presented the superlens concept and the transmissionline model of lefthanded metamaterials. Physics of negative refractive index materials s anantha ramakrishna single metal nanoparticles p zijlstra and m orrit engineering metallic nanostructures for plasmonics and nanophotonics nathan c lindquist, prashant nagpal, kevin m mcpeak et al. Negative refractive index metamaterials sciencedirect. 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. Metamaterials with negative refraction may lead to the development of a superlens capable of imaging objects and fi ne structures that are much smaller than the wavelength of light. The resulting nim refractive index is insensitive to both polarization and angleofincidence over a 50 angular range, yielding a wideangle nim at visible frequencies. Veselago4 suggested that there are materials in which the causal refractive index may be given by another branch of the root n.
A refractive index of zero implies that light enters a state of quasiinfinite phase velocity and infinite wavelength. Nims are constructed of periodic basic parts called unit cells, which are usually significantly smaller than the wavelength of the externally applied electromagnetic. The metamaterial response is confirmed through simulations of planewave refraction through a metamaterial prism. Negative refractive index materials article pdf available in journal of computational and theoretical nanoscience 32. Watson laboratories of applied physics, california. Metamaterials in which the refractive index and the underlying group velocity are both negative this work brings together the best minds in this cuttingedge field. Such an effect can be obtained using a metamaterial which has been designed to achieve a negative value for both electric permittivity. There also exists another kind of metamaterial which includes. Aug 10, 2017 in nature, the only times that you can get a negative index of refraction is with a reflective surface, ie a mirror. However, most of the ideas connected with negative refraction appeared even earlier. Metamaterials and negative refractive index science.
Negative refractive index and acoustic superlens from. Photorealistic images of objects in effective negativeindex. Index terms artificial dielectrics, backward waves, focusing, lefthanded media lhm, metamaterials, negative permeability, negative permittivity, negative refractive index, periodic structures. Negative index of refraction in optical metamaterials. Physics of negative refractive index materials 453 1. Composites with negative refractive index 9 introduction we seek to develop structural composite materials with additional integrated functions. We have discussed the properties and uses of lefthanded metamaterials. Wave propagation in negative index metamaterial here drude model in time domain. 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 2school of electrical and computer engineering, oklahoma state university, stillwater, oklahoma 74078, usa.
Negativeindex metamaterial or negativeindex material nim is a metamaterial whose refractive index for an electromagnetic wave has a negative value over some frequency range. We show that an electromagnetic em wave undergoes negative refraction at the interface between a positive and negative refractive index material. The refractive index retrieval procedure and the critical role of light phases in determining the refractive index is discussed. To identify the signatures of negative refractionfrom a negative refractive index, valentine.
Negative refractive index metamaterials nrm are artificial composites, characteri zed by subwavelength features and negative effective value of re fractive index 2, 3. These materials were theoretically predicted in 1967 by veselago 4 in english translation of his text it is erroneously stated that the first results on this topic were published in 1964. Ever since the first experimental demonstration was reported in 2000, the interest in metamaterials and lefthanded media that exhibit a negative refractive index has increased exponentially. Such behavior results from the plasmon resonance in the pairs of nanorods for both the electric and the magnetic components of light. It also means that every point within the metamaterial. Double negative materials dnm, phenomena and applications. Dionne,1 ewold verhagen, 2 albert polman, and harry a. At the same time, progress was being made in developing different ways of con. Causality and energy density in negative refractive media 476 3. Eleftheriades, periodic analysis of a 2d negative refractive index transmission line structure, ieee trans. Photorealistic images of objects in effective negativeindex materials gunnar dolling and martin wegener institut fur angewandte physik and dfgcenter for functional nanostructures cfn, universitat karlsruhe th, wolfganggaedestrasse 1, d76128 karlsruhe, germany gunnar. Negativerefractiveindex metamaterials using loaded. Artificial magnetism and negative refractive index are two specific types of behavior that have been demonstrated over the past few years, illustrating the new physics and new applications possible. Index terms left handed materials, metamaterials, nanoparticle plasmon resonance, negative refractive index.
Antoniades, negative refractive index transmissionline metamaterials and enabling electromagnetic applications, 2004 ieee antennas and propagation society international. One of the most fundamental notions in optics is that of refractive index, which gives the factor by which the phase velocity of light is decreased in a material compared to vacuum conditions. Negativeindex metamaterial or negativeindex material nim is a metamaterial whose refractive index for an. A new class of materials has created some extraordinary possibilities such as a negative refractive index, and lenses whose resolution is limited only by the precision with which we can. Both experiments and simulations demonstrate that a negative refractive index n0.