The Classical-to-Semiclassical Connection

2017 ◽  
Author(s):  
John A. Adam
Keyword(s):  
Electromagnetic Waves ◽  
Wave Radiation ◽  
Physical Optics ◽  
Incident Plane Wave ◽  
Potential Well ◽  
Intermediate Region ◽  
Symmetric Problem ◽  
Classical Domain ◽  
Incident Plane ◽  
Semiclassical Scattering

This chapter discusses the connection between the classical and semiclassical domains of scattering. Scattering phenomena may be described via three regimes: the scattering of waves by objects with small, large, or comparable sizes with the wavelength of the incident (plane wave) radiation. All three regions can be related to three domains: the classical domain (geometrical optics, particle and particle/ray-like trajectories); the wave domain (physical optics, acoustic and electromagnetic waves, quantum mechanics); and the semiclassical domain (the vast intermediate region between the first and second domain). The chapter first provides an overview of classical and semiclassical scattering domains before beginning with an analysis of the semiclassical formulation. It also considers the radial equation, scattering by a one-dimensional potential barrier, and the radially symmetric problem. Solutions for phase shifts and the potential well are presented.

Voltage and Orientation Dependence of Characteristic X-Ray Production in Thin Crystals

1985 ◽  
Vol 43 ◽  
pp. 414-415
Author(s):  
G. Thomas ◽  
K. M. Krishnan ◽  
Y. Yokota ◽  
H. Hashimoto
Keyword(s):  
Standing Wave ◽  
Incident Beam ◽  
Orientation Dependence ◽  
Incident Plane Wave ◽  
Crystalline Materials ◽  
X Ray ◽  
Incident Plane ◽  
Crystal Unit Cell ◽  
Beam Orientation ◽  
Acceleration Voltage

For crystalline materials, an incident plane wave of electrons under conditions of strong dynamical scattering sets up a standing wave within the crystal. The intensity modulations of this standing wave within the crystal unit cell are a function of the incident beam orientation and the acceleration voltage. As the scattering events (such as inner shell excitations) that lead to characteristic x-ray production are highly localized, the x-ray intensities in turn, are strongly determined by the orientation and the acceleration voltage. For a given acceleration voltage or wavelength of the incident wave, it has been shown that this orientation dependence of the characteristic x-ray emission, termed the “Borrmann effect”, can also be used as a probe for determining specific site occupations of elemental additions in single crystals.

scholarly journals Preparation and electromagnetic properties characterization of reduced graphene oxide/strontium hexaferrite nanocomposites

2020 ◽  
Vol 9 (1) ◽  
pp. 105-114 ◽  
Author(s):  
Shumin Du ◽  
Huaiyin Chen ◽  
Ruoyu Hong
Keyword(s):  
Electromagnetic Wave ◽  
Environmental Pollution ◽  
Electromagnetic Interference ◽  
Electromagnetic Waves ◽  
Rapid Development ◽  
Living Environment ◽  
World Health ◽  
Electromagnetic Properties ◽  
Strontium Hexaferrite ◽  
Wave Radiation

AbstractWith the rapid development of electronics and information technology, electronics and electrical equipment have been widely used in our daily lives. The living environment is full of electromagnetic waves of various frequencies and energy. Electromagnetic wave radiation has evolved into a new type of environmental pollution that has been listed by the WHO (World Health Organization) as the fourth largest source of environmental pollution after water, atmosphere, and noise. Studies have shown that when electromagnetic wave radiation is too much, it can cause neurological disorders. And electromagnetic interference will cause the abnormal operation of medical equipment, precision instruments and other equipment, and therefore cause incalculable consequences. Therefore, electromagnetic protection has become a hot issue of concern to the social and scientific circles.

scholarly journals Core-Shell Nano-Antenna Configurations for Array Formation with More Stability Having Conventional and Non-Conventional Directivity and Propagation Behavior

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 99
Author(s):  
Qaisar Hayat ◽  
Junping Geng ◽  
Xianling Liang ◽  
Ronghong Jin ◽  
Sami Ur Rehman ◽  
...  
Keyword(s):  
Plane Wave ◽  
Propagation Direction ◽  
Core Shell ◽  
Incident Plane Wave ◽  
Polarization Direction ◽  
Shell Nanoparticles ◽  
Incident Plane ◽  
Core Shell Nanoparticles ◽  
Coated Nanoparticle ◽  
2D Array

The enhancement of optical characteristics at optical frequencies deviates with the choice of the arrangement of core-shell nanoparticles and their environment. Likewise, the arrangements of core-shell nanoparticles in the air over a substrate or in liquid solution makes them unstable in the atmosphere. This article suggests designing a configuration of an active spherical coated nanoparticle antenna and its extended array in the presence of a passive dielectric, which is proposed to be extendable to construct larger arrays. The issue of instability in the core-shell nanoantenna array models is solved here by inserting the passive dielectric. In addition to this, the inclusion of a dielectric in the array model reports a different directivity behaviour than the conventional array models. We found at first that the combination model of the active coated nanoparticle and passive sphere at the resonant frequency can excite a stronger field with a rotated polarization direction and a propagation direction different from the incident plane-wave. Furthermore, the extended 2D array also rotates the polarization direction and propagation direction for the vertical incident plane-wave. The radiation beam operates strong multipoles in the 2D array plane at resonant frequency (behaving non-conventionally). Nevertheless, it forms a clear main beam in the incident direction when it deviates from the resonance frequency (behaving conventionally). The proposed array model may have possible applications in nano-amplifiers, nano-sensors and other integrated optics.

Scattering of a Plane Elastic Wave From Objects Near an Interface

1972 ◽  
Vol 39 (4) ◽  
pp. 1019-1026 ◽  
Author(s):  
Stephen B. Bennett
Keyword(s):  
Elastic Wave ◽  
Electromagnetic Waves ◽  
Three Dimensions ◽  
Circular Cylinders ◽  
Scattering Problems ◽  
Reflection And Refraction ◽  
Time Harmonic ◽  
Incident Plane ◽  
Boundary Curves ◽  
Consistent Formulation

The displacement field generated by the reflection and refraction of plane (time harmonic) elastic waves by finite obstacles of arbitrary shape, in the neighborhood of a plane interface between two elastic media, is investigated. The technique employed allows a consistent formulation of the problem for both two and three dimensions, and is not limited either to boundary shapes which are level surfaces in appropriate coordinate systems, i.e., circular cylinders, spheres, etc., or to closed boundary curves or surfaces. The approach is due to Twersky, and has been applied to many problems of the scattering of electromagnetic waves. The method consists of expressing the net field due to all multiple scattering in terms of the field reflected from each boundary in isolation when subjected to an incident plane elastic wave. Thus the technique makes use of more elemental scattering problems whose solutions are extant. By way of illustration, a numerical solution to the scattering of a plane elastic wave by a rigid circular cylindrical obstacle adjacent to a plane free surface is considered.

An accurate theory of X-ray coplanar multiple SRMS diffractometry

2018 ◽  
Vol 74 (6) ◽  
pp. 673-680 ◽  
Author(s):  
V. G. Kohn
Keyword(s):  
Synchrotron Radiation ◽  
Plane Wave ◽  
Experimental Setup ◽  
Incident Plane Wave ◽  
Instrumental Function ◽  
Multiple Diffraction ◽  
Double Crystal ◽  
X Ray ◽  
Double Crystal Monochromator ◽  
Incident Plane

The article reports an accurate theory of X-ray coplanar multiple diffraction for an experimental setup that consists of a generic synchrotron radiation (SR) source, double-crystal monochromator (M) and slit (S). It is called for brevity the theory of X-ray coplanar multiple SRMS diffractometry. The theory takes into account the properties of synchrotron radiation as well as the features of diffraction of radiation in the monochromator crystals and the slit. It is shown that the angular and energy dependence (AED) of the sample reflectivity registered by a detector has the form of a convolution of the AED in the case of the monochromatic plane wave with the instrumental function which describes the angular and energy spectrum of radiation incident on the sample crystal. It is shown that such a scheme allows one to measure the rocking curves close to the case of the monochromatic incident plane wave, but only using the high-order reflections by monochromator crystals. The case of four-beam (220)(331)({\overline {11}}1) diffraction in Si is considered in detail.

Currents and charges induced by a normally incident plane wave on single and crossed tubular cylinders withka= 2

Radio Science ◽  
1978 ◽  
Vol 13 (1) ◽  
pp. 107-119 ◽  
Author(s):  
R. W. P. King ◽  
D. J. Blejer ◽  
S.-K. Wan ◽  
R. W. Burton
Keyword(s):  
Plane Wave ◽  
Incident Plane Wave ◽  
Incident Plane
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