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Author

John B. Pendry

Other affiliations: University of California, San Diego, Duke University, Bell Labs  ...read more
Bio: John B. Pendry is an academic researcher from Imperial College London. The author has contributed to research in topics: Metamaterial & Plasmon. The author has an hindex of 100, co-authored 536 publications receiving 88802 citations. Previous affiliations of John B. Pendry include University of California, San Diego & Duke University.


Papers
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Journal ArticleDOI
TL;DR: In this paper, a nanostructured metallic photonic crystal metamaterial is described and characterized, which is magnetically active in the near-infrared region of the spectrum.
Abstract: We describe and characterize a nanostructured metallic photonic crystal metamaterial which is magnetically active in the near-infrared region of the spectrum. The periodic array of modified split-ring resonator structures is numerically demonstrated to have a negative effective permeability at telecommunications wavelengths. Local electric fields in the structure can be many orders of magnitude larger than in free space thus allowing for enhanced nonlinear effects. We have derived an expression for the change in the resonance frequency of the structure due to the Kerr nonlinear index change and estimate a characteristic magnetic field strength for the observation of bistable behavior.

166 citations

Journal ArticleDOI
TL;DR: In this article, a slab of a medium with negative refractive index bounded by media of different positive refractive indices was shown to act as a near-perfect lens for evanescent waves.
Abstract: We extend the ideas of the perfect lens recently proposed [J.B. Pendry, Phys. Rev. Lett. 85, 3966 (2000)] to an alternative structure. We show that a slab of a medium with negative refractive index bounded by media of different positive refractive index also amplifies evanescent waves and can act as a near-perfect lens. We examine the role of the surface states in the amplification of the evanescent waves. The image resolution obtained by this asymmetric lens is more robust against the effects of absorption in the lens. In particular, we study the case of a slab of silver, which has a negative dielectric constant, with air on one side and other media such as glass or GaAs on the other side as an ‘asymmetric’ lossy near-perfect lens for p-polarized waves. It is found that retardation has an adverse effect on the imaging due to the positive magnetic permeability of silver, but we conclude that subwavelength image resolution is possible in spite of it.

163 citations

Journal ArticleDOI
TL;DR: In this paper, the authors proposed a structure permeated by a fluid and designed so that the composite medium, the metafluid, has an anisotropic density tensor, and a compressibility of choice.
Abstract: Recent theory shows that sound can be controlled and directed almost at will provided that suitable materials can be found. Here, we propose a structure permeated by a fluid and designed so that the composite medium, the metafluid, has an anisotropic density tensor, and a compressibility of choice.

156 citations

Journal ArticleDOI
TL;DR: In this paper, a more circumspect application of intuition shows that transport is dominated by a new sort of band of states, delocalised over a necklace of square root L sites spaced evenly across the material.
Abstract: Intuitive arguments based on the concept of a typical state conclude that transport in localised systems is dominated by the states near the centre of the material. They maximise the transmission coefficient, but have narrow linewidths depending on length, L, as wmin approximately=exp(- delta 1/2L/4). Rigorous 1D theory shows that these arguments are in error. A more circumspect application of intuition shows that transport is dominated by a new sort of band of states, delocalised over a necklace of square root L sites spaced evenly across the material. There are very few of these states; they have fractal dimension 1/2; and they dominate the conductivity because of their large bandwidth: w1/2 approximately=exp(- delta ' square root L). In a typical situation wmin approximately=10-8Hz, w1/2 approximately=106 Hz. Whereas the rigorous results are derived only in the 1D case, the intuitive arguments are valid for strongly localised systems irrespective of dimension.

145 citations


Cited by
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28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal ArticleDOI
14 Aug 2003-Nature
TL;DR: By altering the structure of a metal's surface, the properties of surface plasmons—in particular their interaction with light—can be tailored, which could lead to miniaturized photonic circuits with length scales that are much smaller than those currently achieved.
Abstract: Surface plasmons are waves that propagate along the surface of a conductor. By altering the structure of a metal's surface, the properties of surface plasmons--in particular their interaction with light--can be tailored, which offers the potential for developing new types of photonic device. This could lead to miniaturized photonic circuits with length scales that are much smaller than those currently achieved. Surface plasmons are being explored for their potential in subwavelength optics, data storage, light generation, microscopy and bio-photonics.

10,689 citations

Journal ArticleDOI
06 Apr 2001-Science
TL;DR: These experiments directly confirm the predictions of Maxwell's equations that n is given by the negative square root ofɛ·μ for the frequencies where both the permittivity and the permeability are negative.
Abstract: We present experimental scattering data at microwave frequencies on a structured metamaterial that exhibits a frequency band where the effective index of refraction (n) is negative. The material consists of a two-dimensional array of repeated unit cells of copper strips and split ring resonators on interlocking strips of standard circuit board material. By measuring the scattering angle of the transmitted beam through a prism fabricated from this material, we determine the effective n, appropriate to Snell's law. These experiments directly confirm the predictions of Maxwell's equations that n is given by the negative square root of epsilon.mu for the frequencies where both the permittivity (epsilon) and the permeability (mu) are negative. Configurations of geometrical optical designs are now possible that could not be realized by positive index materials.

8,477 citations

Journal ArticleDOI
TL;DR: In this paper, it was shown that microstructures built from nonmagnetic conducting sheets exhibit an effective magnetic permeability /spl mu/sub eff/, which can be tuned to values not accessible in naturally occurring materials.
Abstract: We show that microstructures built from nonmagnetic conducting sheets exhibit an effective magnetic permeability /spl mu//sub eff/, which can be tuned to values not accessible in naturally occurring materials, including large imaginary components of /spl mu//sub eff/. The microstructure is on a scale much less than the wavelength of radiation, is not resolved by incident microwaves, and uses a very low density of metal so that structures can be extremely lightweight. Most of the structures are resonant due to internal capacitance and inductance, and resonant enhancement combined with compression of electrical energy into a very small volume greatly enhances the energy density at critical locations in the structure, easily by factors of a million and possibly by much more. Weakly nonlinear materials placed at these critical locations will show greatly enhanced effects raising the possibility of manufacturing active structures whose properties can be switched at will between many states.

8,135 citations

Journal ArticleDOI
TL;DR: Recent advances at the intersection of plasmonics and photovoltaics are surveyed and an outlook on the future of solar cells based on these principles is offered.
Abstract: The emerging field of plasmonics has yielded methods for guiding and localizing light at the nanoscale, well below the scale of the wavelength of light in free space. Now plasmonics researchers are turning their attention to photovoltaics, where design approaches based on plasmonics can be used to improve absorption in photovoltaic devices, permitting a considerable reduction in the physical thickness of solar photovoltaic absorber layers, and yielding new options for solar-cell design. In this review, we survey recent advances at the intersection of plasmonics and photovoltaics and offer an outlook on the future of solar cells based on these principles.

8,028 citations