scholarly journals Linked Weyl surfaces and Weyl arcs in photonic metamaterials

Science ◽  
2021 ◽  
Vol 373 (6554) ◽  
pp. 572-576
Author(s):  
Shaojie Ma ◽  
Yangang Bi ◽  
Qinghua Guo ◽  
Biao Yang ◽  
Oubo You ◽  
...  
Keyword(s):  
Electromagnetic Waves ◽  
Three Dimensional ◽  
Electromagnetic Properties ◽  
Higher Dimension ◽  
Surface Phenomena ◽  
Physical Systems ◽  
Higher Dimensional ◽  
Topological Singularities ◽  
Lower Dimensional

Generalization of the concept of band topology from lower-dimensional to higher-dimensional (n > 3) physical systems is expected to introduce new bulk and boundary topological effects. However, theoretically predicted topological singularities in five-dimensional systems—Weyl surfaces and Yang monopoles—have either not been demonstrated in realistic physical systems or are limited to purely synthetic dimensions. We constructed a system possessing Yang monopoles and Weyl surfaces based on metamaterials with engineered electromagnetic properties, leading to the observation of several intriguing bulk and surface phenomena, such as linking of Weyl surfaces and surface Weyl arcs, via selected three-dimensional subspaces. The demonstrated photonic Weyl surfaces and Weyl arcs leverage the concept of higher-dimension topology to control the propagation of electromagnetic waves in artificially engineered photonic media.

The Structure of the Polytope of Hereditary Information

2019 ◽  
Vol 8 (2) ◽  
pp. 7-22
Author(s):  
Gennadiy Vladimirovich Zhizhin
Keyword(s):  
Nucleic Acid ◽  
Hydrogen Bonds ◽  
Phosphoric Acid ◽  
High Intensity ◽  
Information Exchange ◽  
Three Dimensional ◽  
Higher Dimension ◽  
Nitrogen Bases ◽  
Higher Dimensional ◽  
Low Dimensional

The representations of the sugar molecule and the residue of phosphoric acid in the form of polytopes of higher dimension are used. Based on these ideas and their simplified three-dimensional images, a three-dimensional image of nucleic acids is constructed. The geometry of the neighborhood of the compound of two nucleic acid helices with nitrogen bases has been investigated in detail. It is proved that this neighborhood is a cross-polytope of dimension 13 (polytope of hereditary information), in the coordinate planes of which there are complementary hydrogen bonds of nitrogenous bases. The structure of this polytope is defined, and its image is given. The total incident flows from the low-dimensional elements to the higher-dimensional elements and vice versa of the hereditary information polytope are calculated equal to each other. High values of these flows indicate a high intensity of information exchange in the polytope of hereditary information that ensures the transfer of this information.

scholarly journals INTERACTING INTERSECTIONS

1998 ◽  
Vol 13 (25) ◽  
pp. 4425-4443 ◽  
Author(s):  
H. LÜ ◽  
C. N. POPE
Keyword(s):  
Binding Energy ◽  
Harmonic Functions ◽  
Periodic Array ◽  
Higher Dimension ◽  
Higher Dimensional ◽  
The Individual ◽  
Natural Description ◽  
Lower Dimensional

Intersecting p-branes can be viewed as higher-dimensional interpretations of multicharge extremal p-branes, where some of the individual p-branes undergo diagonal dimensional oxidation, while the others oxidize vertically. Although the naive vertical oxidation of a single p-brane gives a continuum of p-branes, a more natural description arises if one considers a periodic array of p-branes in the higher dimension, implying a dependence on the compactification coordinates. This still reduces to the single lower-dimensional p-brane when viewed at distances large compared with the period. Applying the same logic to the multicharge solutions, we are led to consider more general classes of intersecting p-brane solutions, again depending on the compactification coordinates, which turn out to be described by interacting functions rather than independent harmonic functions. These new solutions also provide a more satisfactory interpretation for the lower-dimensional multicharge p-branes, which otherwise appear to be nothing more than the improbable coincidence of charge-centres of individual constituents with zero binding energy.

scholarly journals A Review on Additive Manufacturing Possibilities for Electrical Machines

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1940
Author(s):  
Muhammad Usman Naseer ◽  
Ants Kallaste ◽  
Bilal Asad ◽  
Toomas Vaimann ◽  
Anton Rassõlkin
Keyword(s):  
Additive Manufacturing ◽  
Large Scale ◽  
Three Dimensional ◽  
Electrical Machines ◽  
Electromagnetic Properties ◽  
Scale Production ◽  
Performance Parameters ◽  
Large Scale Production ◽  
One Step ◽  
Manufacturing Techniques

This paper presents current research trends and prospects of utilizing additive manufacturing (AM) techniques to manufacture electrical machines. Modern-day machine applications require extraordinary performance parameters such as high power-density, integrated functionalities, improved thermal, mechanical & electromagnetic properties. AM offers a higher degree of design flexibility to achieve these performance parameters, which is impossible to realize through conventional manufacturing techniques. AM has a lot to offer in every aspect of machine fabrication, such that from size/weight reduction to the realization of complex geometric designs. However, some practical limitations of existing AM techniques restrict their utilization in large scale production industry. The introduction of three-dimensional asymmetry in machine design is an aspect that can be exploited most with the prevalent level of research in AM. In order to take one step further towards the enablement of large-scale production of AM-built electrical machines, this paper also discusses some machine types which can best utilize existing developments in the field of AM.

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 Electromagnetic Properties of Disordered Three-Dimensional Mixtures

IEEE Access ◽  
2013 ◽  
Vol 1 ◽  
pp. 778-788 ◽  
Author(s):  
Austin J. Pickles ◽  
Ian M. Kilgore ◽  
Michael B. Steer
Keyword(s):  
Three Dimensional ◽  
Electromagnetic Properties

Stability and instability of some nonlinear dispersive solitary waves in higher dimension

1996 ◽  
Vol 126 (1) ◽  
pp. 89-112 ◽  
Author(s):  
Anne de Bouard
Keyword(s):  
Solitary Waves ◽  
Acoustic Waves ◽  
Vries Equation ◽  
Three Dimensional ◽  
Higher Dimension ◽  
Ion Acoustic Waves ◽  
Stability And Instability ◽  
Ion Acoustic ◽  
De Vries ◽  
The Stability

We study the stability of positive radially symmetric solitary waves for a three dimensional generalisation of the Korteweg de Vries equation, which describes nonlinear ion-acoustic waves in a magnetised plasma, and for a generalisation in dimension two of the Benjamin–Bona–Mahony equation.

scholarly journals GRAVITY-WAVE DETECTORS AS PROBES OF EXTRA DIMENSIONS

2005 ◽  
Vol 14 (12) ◽  
pp. 2347-2353 ◽  
Author(s):  
CHRIS CLARKSON ◽  
ROY MAARTENS
Keyword(s):  
Black Holes ◽  
String Theory ◽  
Gravity Wave ◽  
Gravity Waves ◽  
Extra Dimensions ◽  
State Of The Art ◽  
Three Dimensional ◽  
Observable Universe ◽  
Dimensional Spacetime ◽  
Higher Dimensional

If string theory is correct, then our observable universe may be a three-dimensional "brane" embedded in a higher-dimensional spacetime. This theoretical scenario should be tested via the state-of-the-art in gravitational experiments — the current and upcoming gravity-wave detectors. Indeed, the existence of extra dimensions leads to oscillations that leave a spectroscopic signature in the gravity-wave signal from black holes. The detectors that have been designed to confirm Einstein's prediction of gravity waves, can in principle also provide tests and constraints on string theory.

MXene nanohybrids: Excellent electromagnetic properties for absorbing electromagnetic waves

2021 ◽  
Author(s):  
Peng He ◽  
Meng-Jiao Zheng ◽  
Qi Liu ◽  
Zi-Yi Liu ◽  
Ru-Zhong Zuo ◽  
...  
Keyword(s):  
Electromagnetic Waves ◽  
Electromagnetic Properties

Theory to Help the Use of Electromagnetic Flow Meters

2002 ◽  
Author(s):  
Xiao-Zhang Zhang
Keyword(s):  
Pipe Wall ◽  
Three Dimensional ◽  
Electromagnetic Properties ◽  
Reasonable Accuracy ◽  
Flow Meter ◽  
Flow Meters ◽  
Electromagnetic Flow ◽  
Gas Liquid Flow ◽  
Electromagnetic Flow Meter ◽  
Theory Research

Compared with other flow meters, the theory of electromagnetic flow meter is well developed. Until now, we are able to predict the three dimensional characteristics of this kind of flow meters with reasonable accuracy. This has given much help to the designers to improve the flow meters. On the other hand, the theory can offer a tool for the users of this kind of flow meters to judge the application situations, estimate the possible measurement error, etc. This paper introduces the recent work of the author on the theory of the electromagnetic flow meter. The basic physical conceptions and equations are given with a brief history review of the theory research. Several examples are given of using the theory to analyze the meters’ behavior in different application situations. They are: effect of the conducting pipe connections; errors caused by a pipe wall of different electromagnetic properties; gas-liquid flow and errors caused by a relative motion of the probe.

NONRECIPROCAL ELECTROMAGNETIC DEVICES IN GYROMAGNETIC PHOTONIC CRYSTALS

2013 ◽  
Vol 28 (02) ◽  
pp. 1441010 ◽  
Author(s):  
ZHI-YUAN LI ◽  
RONG-JUAN LIU ◽  
LIN GAN ◽  
JIN-XIN FU ◽  
JIN LIAN
Keyword(s):  
Magnetic Field ◽  
Band Gap ◽  
Electromagnetic Waves ◽  
Experimental Studies ◽  
Magnetic Surface ◽  
Electromagnetic Properties ◽  
Edge States ◽  
Bragg Scattering ◽  
Electromagnetic Devices ◽  
Gap Opening

Gyromagnetic photonic crystal (GPC) offers a promising way to realize robust transport of electromagnetic waves against backscattering from various disorders, perturbations and obstacles due to existence of unique topological electromagnetic states. The dc magnetic field exerting upon the GPC brings about the time-reversal symmetry breaking, splits the band degeneracy and opens band gaps where the topological chiral edge states (CESs) arise. The band gap can originate either from long-range Bragg-scattering effect or from short-range localized magnetic surface plasmon resonance (MSP). These topological edge states can be explored to construct backscattering-immune one-way waveguide and other nonreciprocal electromagnetic devices. In this paper we review our recent theoretical and experimental studies of the unique electromagnetic properties of nonreciprocal devices built in GPCs. We will discuss various basic issues like experimental instrumental setup, sample preparations, numerical simulation methods, tunable properties against magnetic field, band degeneracy breaking and band gap opening and creation of topological CESs. We will investigate the unidirectional transport properties of one-way waveguide under the influence of waveguide geometries, interface morphologies, intruding obstacles, impedance mismatch, lattice disorders, and material dissipation loss. We will discuss the unique coupling properties between one-wave waveguide and resonant cavities and their application as novel one-way bandstop filter and one-way channel-drop filter. We will also compare the CESs created in the Bragg-scattering band gap and the MSP band gap under the influence of lattice disorders. These results can be helpful for designing and exploring novel nonreciprocal electromagnetic devices for optical integration and information processing.

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