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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 article, an ultrathin plasmonic grating made of a gold grating covered by a thin flat layer of gold was proposed to achieve bianisotropy at visible wavelengths.
Abstract: We present a simple design to achieve bianisotropy at visible wavelengths: an ultrathin plasmonic grating made of a gold grating covered by a thin flat layer of gold. We show experimentally and through simulations that the grating exhibits magnetoelectric coupling and features asymmetric reflection and absorption, all that with a device thickness of a tenth of the operating wavelength. We compared the spectral results and retrieved the effective material parameters of different polarizations and devices. We show that both asymmetry and strong coupling between the incoming light and the optically interacting surfaces are required for obtaining asymmetric optical behavior in metasurfaces.

11 citations

Journal ArticleDOI
TL;DR: In this paper, the authors considered the absorption spectrum in two parts: the EXAFS, beyond about 50 eV above the absorption edge, and the x-ray absorption near edge structure (XANES), within about 50 EV of threshold.
Abstract: An absorption spectrum can be considered in two parts: the EXAFS, beyond about 50 eV above the absorption edge, and the x‐ray absorption near edge structure (XANES), within about 50 eV of threshold. Although there is no exact division, and the figure of 50 eV is somewhat arbitrary, there are real physical differences between the two parts of the spectrum. In the EXAFS region, scattering is weak, electron mean‐free‐paths are short, and phase‐shifts are readily calculable or transferable from model compounds. The single scattering approximation holds good, and bond lengths can be derived from Fourier transform analysis of the data, but the spectrum contains information only on pairwise atomic correlations. By contrast, in the XANES regime, scattering is strong and mean‐free‐paths are long, making multiple scattering important and data analysis difficult, but the spectrum in consequence is rich in information on three‐body and other correlations.

11 citations

Journal ArticleDOI
TL;DR: In this article, the authors evaluated the contribution of thermal vibrations to the inelastic contribution to the diffuse intensity of a tensor LEED system using a linear version of the tensor tensor leed technique.

10 citations

Journal ArticleDOI
TL;DR: In this article, a criterion is developed for the number of charges transported per ion and contrasts are made between transport in ionic and metallic states in terms of transport in both ion and metal states.
Abstract: Measurements and calculations of static ionic charge density show a strong overlap of the charge both with the anions and the cations. Despite this sharing of charge, the authors show how to explain the transport of charge in integer units in quantum mechanical terms. A criterion is developed for the number of charges transported per ion and contrasts are made between transport in ionic and metallic states.

10 citations

Journal ArticleDOI
TL;DR: In this article, an ultrathin plasmonic grating made of a gold grating covered by a thin flat layer of gold was proposed to achieve bianisotropy at visible wavelengths.
Abstract: We present a simple design to achieve bianisotropy at visible wavelengths: an ultrathin plasmonic grating made of a gold grating covered by a thin flat layer of gold. We show experimentally and through simulations that the grating exhibits magneto-electric coupling and features asymmetric reflection and absorption, all that with a device thickness of a tenth of the operating wavelength. We compared the spectral results and retrieved the effective material parameters of different polarizations and devices. We show that both asymmetry and strong coupling between the incoming light and the optically interacting surfaces are required for obtaining asymmetric optical behavior in metasurfaces.

10 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