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Near and far field

About: Near and far field is a research topic. Over the lifetime, 15922 publications have been published within this topic receiving 220571 citations.


Papers
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Journal ArticleDOI
TL;DR: In this article, a review of the status of problems involving the interaction of matter and optical-band electromagnetic radiation of intensity such that any medium becomes a fully ionized plasma is presented.
Abstract: A review is presented of the status of problems involving the interaction of matter and optical-band electromagnetic radiation of intensity such that any medium becomes a fully ionized plasma. The following are considered within the framework of the single-electron approximation in the case of nonrelativistic energies: stimulated bremsstrahlung and absorption of an electron in the field of a strong electromagnetic wave, stimulated two-photon Compton scattering, and scattering of electrons in the field of an intense standing electromagnetic wave (the Kapitza-Dirac effect). The role played by these processes in the heating of plasma by laser radiation is analyzed, as is the question of the possibility of obtaining amplification (negative absorption) of light in transitions in a continuous spectrum. The bibliography is brought up to date to the middle of 1971.

81 citations

Journal ArticleDOI
TL;DR: In this paper, an exact analytical expression for the magnetic field of a cylinder of finite length with a uniform, transverse magnetization was derived, and validated against the well-known limits of an infinitely long cylinder, the field on the axis of the cylinder and in the far field limit.

81 citations

Journal ArticleDOI
TL;DR: In this article, an analytical-numerical technique for the solution of the two-dimensional electromagnetic plane-wave scattering by a finite set of perfectly conducting circular cylinders buried in a dielectric half-space is presented.
Abstract: An analytical-numerical technique, for the solution of the two-dimensional electromagnetic plane-wave scattering by a finite set of perfectly conducting circular cylinders buried in a dielectric half-space, is presented. The problem is solved for both the near- and the far-field regions, for TM and TE polarizations. The diffracted field is represented in terms of a superposition of cylindrical waves and use is made of the plane-wave spectrum to take into account the reflection and transmission of such waves by the interface. The validity of the approach is confirmed by comparisons with results available in the literature, with very good agreement. The multiple interactions between two buried cylinders have been studied by considering both the induced currents and the scattered field diagrams. Applications of the method to objects of arbitrary cross-section simulated by a suitable configuration of circular cylinders are shown.

81 citations

Patent
20 Jun 1991
TL;DR: An acoustic microscope assembly for atomic level inspection of a target object includes a cantilever arm with a sharp tip on its lower surface and a zinc oxide piezoelectric thin film on its upper surface.
Abstract: An acoustic microscope assembly for atomic level inspection of a target object includes a cantilever arm with a sharp tip on its lower surface and a zinc oxide piezoelectric thin film on its upper surface. High frequency excitation signals, having a frequency of at least 50 Megahertz, are applied to the piezoelectric thin film so as to generate high frequency acoustic signals that are transmitted through the sharp tip so as to impact on a target object. The assembly can either receive acoustic signals reflected by the target object, or it can receive acoustic signals that have propagated through the target object. One method of using this assembly is to apply a continuous wave signal to the piezoelectric thin film while scanning the target object, and measuring characteristics of the target object at various positions thereof by measuring the resonant frequency of the transmitted high frequency acoustic signals. Other methods include pulsed operation, and combining acoustic measurements with atomic force measurements and/or tunneling current measurements to characterize a target object. The acoustic microscope assembly can also be used for storing information on a substrate, by deforming the substrate at selected positions, and for reading such stored information by determining which positions on a substrate have been deformed.

81 citations

Journal ArticleDOI
TL;DR: In this article, the problem of the electromagnetic shielding effectiveness of a thin, plane metal sheet of infinite extent on the electromagnetic field generated by a circular loop field source with uniform current I is solved by application of the quasi-near and near field approximations to the exact integral expressions.
Abstract: The problem of the electromagnetic shielding effectiveness of a thin, plane metal sheet of infinite extent on the electromagnetic field generated by a circular loop field source with uniform current I is solved by application of the quasi-near and near field approximations to the exact integral expressions. The results are shown to be in close agreement with experimental data as well as numerical integration results. Also, they are similar to the results obtained from the plane wave shielding theory of Schelkunoff.

81 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023132
2022281
2021376
2020460
2019640
2018604