The dispersion characteristics for magnetostatic surface waves in a left handed ( LHM)/ferrite/ metal-stripgrating
structure have been investigated. We found that, the waveguide supports backward TE waves
since both permittivity and magnetic permeability of LHM are negative. We also illustrated the
dependence of wave frequency on the reduced wave number for a grating shielding parameter, g values
restricted by the range 0 ≤ g ≥ 1. It is shown that the grating shielding parameter, g induces
magnetostatic backward shorter waves . The leakage through the grating increases with the wave number. The shorter backward magnetostatic waves are guided by the thicker waveguide where the best confinement is achieved
Stability Of Magnetostatic Surface Waves In A Semiconductor-Ferrite-Left-Hand...ijrap
Recently increasing works have been devoted to study and fabricate new artificial materials called
metamaterials or left handed materials. These materials have unusual behavior as they have
simultaneously both negative permittivity and permeability.
In this paper, we investigate the effect of left handed materials and the conductivity of semiconductor
material on the dispersion characteristics of left-handed-ferrite-semiconductor waveguide structure, and
then we discuss the stability of magnetostatic surface waves in the mentioned three waveguide structures by
perturbation method.
SURFACE POLARITONS IN GAAS/ALGAAS/LH HETROJUNCTION STRUCTURE IN A HIGH MAGNET...ijrap
The surface polaritons (SP) variation in Ga As/ Al Ga As/ LH hetrojunction composition in the presence of
a strong transverse quantized magnetic field is estimated using the quantum Hall effect case. The
dispersion characteristics of the SPs are investigated using the dielectric constants values of the Ga As and
the Alx Ga 1-x As media and the defined thickness, the Alx Ga 1-x As medium. The dispersion behaviours
calculated results are listed for considered cases. It was shown that the frequency values against the wave
vector values are affected in a strong manner by changing thickness, of the Alx
Ga 1-x- As media and by
changing the variation of the dielectric constants of Ga As against the Alx Ga 1-x As. The significance
effects of the use of the left-handed (LH) medium as an upper layer of the proposed composition was
demonstrated; the frequency values are remarkably increased using LH material as an upper layer. It was
noticed that at certain conditions of the LH upper layer composition, similar results have been obtained
such as found by using dielectric upper layer.
Simulation Analysis of Single Column Plate Phononic Crystals At Low Frequency...IJRESJOURNAL
ABSTRACT: In this paper, locally resonant single side column plate phononic crystals are studied. Based on the finite element method, the material properties of the scatterer and the effect of the plate shape on the band gap characteristics of the locally resonant single side column plate phononic crystals are calculated and analyzed by use of the multi-physics software COMSOL. Based on the analysis on the effects of the density, the elastic modulus, the poisson ratio and the shape of the scatterer, it is shown that the density, the elastic modulus and the shape of the scatterer can obviously affect the band gaps of phononiccrystals .
Analysis and Design of One Dimensional Periodic Foundations for Seismic Base ...IJERA Editor
Periodic foundationis a new type of seismic base isolation system. It is inspired by the periodic material crystal
lattice in the solid state physics. This kind of material has a unique property, which is termed as frequency band
gap that is capable of blocking incoming waves having frequencies falling within the band gap. Consequently,
seismic waves having frequencies falling within the frequency band gap are blocked by the periodic foundation.
The ability to block the seismic waveshas put this kind of foundation as a prosperous next generation of seismic
base isolators. This paper provides analytical study on the one dimensional (1D) type periodic foundations to
investigate their seismic performance. The general idea of basic theory of one dimensional (1D) periodic
foundations is first presented.Then, the parametric studies considering infinite and finite boundary conditions are
discussed. The effect of superstructure on the frequency band gap is investigated as well. Based on the analytical
study, a set of equations is proposed for the design guidelines of 1D periodic foundations for seismic base
isolation of structures.
Stability Of Magnetostatic Surface Waves In A Semiconductor-Ferrite-Left-Hand...ijrap
Recently increasing works have been devoted to study and fabricate new artificial materials called
metamaterials or left handed materials. These materials have unusual behavior as they have
simultaneously both negative permittivity and permeability.
In this paper, we investigate the effect of left handed materials and the conductivity of semiconductor
material on the dispersion characteristics of left-handed-ferrite-semiconductor waveguide structure, and
then we discuss the stability of magnetostatic surface waves in the mentioned three waveguide structures by
perturbation method.
SURFACE POLARITONS IN GAAS/ALGAAS/LH HETROJUNCTION STRUCTURE IN A HIGH MAGNET...ijrap
The surface polaritons (SP) variation in Ga As/ Al Ga As/ LH hetrojunction composition in the presence of
a strong transverse quantized magnetic field is estimated using the quantum Hall effect case. The
dispersion characteristics of the SPs are investigated using the dielectric constants values of the Ga As and
the Alx Ga 1-x As media and the defined thickness, the Alx Ga 1-x As medium. The dispersion behaviours
calculated results are listed for considered cases. It was shown that the frequency values against the wave
vector values are affected in a strong manner by changing thickness, of the Alx
Ga 1-x- As media and by
changing the variation of the dielectric constants of Ga As against the Alx Ga 1-x As. The significance
effects of the use of the left-handed (LH) medium as an upper layer of the proposed composition was
demonstrated; the frequency values are remarkably increased using LH material as an upper layer. It was
noticed that at certain conditions of the LH upper layer composition, similar results have been obtained
such as found by using dielectric upper layer.
Simulation Analysis of Single Column Plate Phononic Crystals At Low Frequency...IJRESJOURNAL
ABSTRACT: In this paper, locally resonant single side column plate phononic crystals are studied. Based on the finite element method, the material properties of the scatterer and the effect of the plate shape on the band gap characteristics of the locally resonant single side column plate phononic crystals are calculated and analyzed by use of the multi-physics software COMSOL. Based on the analysis on the effects of the density, the elastic modulus, the poisson ratio and the shape of the scatterer, it is shown that the density, the elastic modulus and the shape of the scatterer can obviously affect the band gaps of phononiccrystals .
Analysis and Design of One Dimensional Periodic Foundations for Seismic Base ...IJERA Editor
Periodic foundationis a new type of seismic base isolation system. It is inspired by the periodic material crystal
lattice in the solid state physics. This kind of material has a unique property, which is termed as frequency band
gap that is capable of blocking incoming waves having frequencies falling within the band gap. Consequently,
seismic waves having frequencies falling within the frequency band gap are blocked by the periodic foundation.
The ability to block the seismic waveshas put this kind of foundation as a prosperous next generation of seismic
base isolators. This paper provides analytical study on the one dimensional (1D) type periodic foundations to
investigate their seismic performance. The general idea of basic theory of one dimensional (1D) periodic
foundations is first presented.Then, the parametric studies considering infinite and finite boundary conditions are
discussed. The effect of superstructure on the frequency band gap is investigated as well. Based on the analytical
study, a set of equations is proposed for the design guidelines of 1D periodic foundations for seismic base
isolation of structures.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Wave propagation in viscoelastic wedge with an arbitrary angle peaksIJRES Journal
Modeling of wave propagation in bodies with different geometrical form, is an urgent task. Of
particular interest is the construction of the dispersion curves for the deformable wedge considering rheological
properties of the material. The aim of this work is a theoretical study of changes in the complex phase velocity of
the wave number. The object of this study is deformable wedge. Wedge material is linearly viscoelastic. Boundary
value problem for a system of differential equations is solved using the method of lines, which allows you to use
the method of orthogonal sweep Godunov and Mueller. The calculation results obtained on the
dimensionless quantities. The viscoelastic properties of the material are described by the three-parameter
relaxation kernel Koltunov - Ryzhanitsen. For the numerical implementation of the problem, use a tool MAPLE
9.5. The results of calculations are compared with the known data [2], and differ by 6-20%. Accounting for the
viscoelastic properties of the material of the wedge increases the real part of the wave propagation velocity is 10-
15%, and also allows to evaluate the damping of the system as a whole. It is found that for small wedge angles
allowed the use of the simplified theory of Kirchhoff - Love and Timoshenko throughout the wavelength range.
An advanced DFT based methodology applied to
(VASP, Quantum Espresso, WIEN2K)
1) higher atomic number containing complex oxides to understand metal to insulator transition.
2) when we add d electron containing atoms (e.g. iron, cobalt etc.) on oxide surfaces they exhibit surprises
In both the cases, this work shows how to complement experiment by theory
How Carbon Nanotubes Collapse on Different Ag Surface?ijrap
The collapse and stability of carbon nanotubes (CNTs) on noble metal silver different surfaces were studied
using molecular mechanics and molecular dynamics simulations. From the results, it can be seen that the
CNTs can collapse spontaneously onto different silver surface [(1 0 0), (1 1 0), (1 1 1)] due to the van der
Waals force between them. Furthermore, the CNT collapsing on (1 0 0) and (1 1 1) surface are much easier
than that on (1 1 0) surface. Moreover, the results show that the collapsed CNTs exhibit as linked graphene
ribbons and have the largest area to contact with the Ag surface, which greatly enhances adhesion between
the CNTs and the Ag surface and keeps the system much more stable.
Ultrasonic guided wave techniques have great potential for structural health monitoring applications. Appropriate mode and frequency selection is the basis for achieving optimised damage monitoring performance.
In this paper, several important guided wave mode attributes are
introduced in addition to the commonly used phase velocity and group velocity dispersion curves while using the general corrosion problem as an example. We first derive a simple and generic wave excitability function based on the theory of normal mode expansion and the reciprocity theorem. A sensitivity dispersion curve is formulated based on the group velocity dispersion curve. Both excitability and sensitivity dispersion curves are verified with finite element simulations. Finally, a
goodness dispersion curve concept is introduced to evaluate the tradeoffs between multiple mode selection objectives based on the wave velocity, excitability and sensitivity.
Sliding motion and adhesion control through magnetic domaminsAndrea Benassi
Actuation and control of motion in micro mechanical systems are technological challenges, since they are accompanied by mechanical friction and wear, principal and well known sources of device lifetime reduction. In this theoretical work we propose a non-contact motion control technique based on the introduction of a tunable magnetic interaction. The latter is realized by coating two non-touching sliding bodies with ferromagnetic films. The resulting dynamics is determined by shape, size and ordering of magnetic domains arising in the films below the Curie temperature. We demonstrate that the domain behavior can be tailored by acting on handles like ferromagnetic coating preparation, external magnetic fields and the finite distance between the plates. In this way, motion control can be achieved without mechanical contact. Moreover, we discuss how such handles can disclose a variety of sliding regimes. Finally, we propose how to practically implement the proposed model sliding system.
A COMPARATIVE STUDY OF VARIOUS METHODS TO EVALUATE IMPEDANCE FUNCTION FOR SHA...Samirsinh Parmar
Impedance function, Foundation Vibration, dynamic soil-structure interaction, Barkan, Dominguez, Dobry and Gazetas for evaluation of impedance functions for various modes of vibration of shallow foundation
Magnetostatic Surface Waves in a Left Handed / Ferrite/ Metal-Strip-Grating ...ijrap
The dispersion characteristics for magnetostatic surface waves in a left handed ( LHM)/ferrite/ metal-stripgrating structure have been investigated. We found that, the waveguide supports backward TE waves
since both permittivity and magnetic permeability of LHM are negative. We also illustrated the
dependence of wave frequency on the reduced wave number for a grating shielding parameter, g values
restricted by the range 0 ≤ g ≥ 1. It is shown that the grating shielding parameter, g induces
magnetostatic backward shorter waves . The leakage through the grating increases with the wave number.
The shorter backward magnetostatic waves are guided by the thicker waveguide where the best
confinement is achieved .
Stability Of Magnetostatic Surface Waves In A Semiconductor-Ferrite-Left-Hand...ijrap
Recently increasing works have been devoted to study and fabricate new artificial materials called
metamaterials or left handed materials. These materials have unusual behavior as they have
simultaneously both negative permittivity and permeability.
In this paper, we investigate the effect of left handed materials and the conductivity of semiconductor
material on the dispersion characteristics of left-handed-ferrite-semiconductor waveguide structure, and
then we discuss the stability of magnetostatic surface waves in the mentioned three waveguide structures by
perturbation method.
Surface Polaritons in GAAS/ALGAAS/LH Hetrojunction Structure in a High Magnet...ijrap
The surface polaritons (SP) variation in Ga As/ Al Ga As/ LH hetrojunction composition in the presence of
a strong transverse quantized magnetic field is estimated using the quantum Hall effect case. The
dispersion characteristics of the SPs are investigated using the dielectric constants values of the Ga As and
the Alx Ga 1-x As media and the defined thickness, the Alx Ga 1-x As medium. The dispersion behaviours
calculated results are listed for considered cases. It was shown that the frequency values against the wave
vector values are affected in a strong manner by changing thickness, of the Alx
Ga 1-x- As media and by
changing the variation of the dielectric constants of Ga As against the Alx Ga 1-x As. The significance
effects of the use of the left-handed (LH) medium as an upper layer of the proposed composition was
demonstrated; the frequency values are remarkably increased using LH material as an upper layer. It was
noticed that at certain conditions of the LH upper layer composition, similar results have been obtained
such as found by using dielectric upper layer.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Wave propagation in viscoelastic wedge with an arbitrary angle peaksIJRES Journal
Modeling of wave propagation in bodies with different geometrical form, is an urgent task. Of
particular interest is the construction of the dispersion curves for the deformable wedge considering rheological
properties of the material. The aim of this work is a theoretical study of changes in the complex phase velocity of
the wave number. The object of this study is deformable wedge. Wedge material is linearly viscoelastic. Boundary
value problem for a system of differential equations is solved using the method of lines, which allows you to use
the method of orthogonal sweep Godunov and Mueller. The calculation results obtained on the
dimensionless quantities. The viscoelastic properties of the material are described by the three-parameter
relaxation kernel Koltunov - Ryzhanitsen. For the numerical implementation of the problem, use a tool MAPLE
9.5. The results of calculations are compared with the known data [2], and differ by 6-20%. Accounting for the
viscoelastic properties of the material of the wedge increases the real part of the wave propagation velocity is 10-
15%, and also allows to evaluate the damping of the system as a whole. It is found that for small wedge angles
allowed the use of the simplified theory of Kirchhoff - Love and Timoshenko throughout the wavelength range.
An advanced DFT based methodology applied to
(VASP, Quantum Espresso, WIEN2K)
1) higher atomic number containing complex oxides to understand metal to insulator transition.
2) when we add d electron containing atoms (e.g. iron, cobalt etc.) on oxide surfaces they exhibit surprises
In both the cases, this work shows how to complement experiment by theory
How Carbon Nanotubes Collapse on Different Ag Surface?ijrap
The collapse and stability of carbon nanotubes (CNTs) on noble metal silver different surfaces were studied
using molecular mechanics and molecular dynamics simulations. From the results, it can be seen that the
CNTs can collapse spontaneously onto different silver surface [(1 0 0), (1 1 0), (1 1 1)] due to the van der
Waals force between them. Furthermore, the CNT collapsing on (1 0 0) and (1 1 1) surface are much easier
than that on (1 1 0) surface. Moreover, the results show that the collapsed CNTs exhibit as linked graphene
ribbons and have the largest area to contact with the Ag surface, which greatly enhances adhesion between
the CNTs and the Ag surface and keeps the system much more stable.
Ultrasonic guided wave techniques have great potential for structural health monitoring applications. Appropriate mode and frequency selection is the basis for achieving optimised damage monitoring performance.
In this paper, several important guided wave mode attributes are
introduced in addition to the commonly used phase velocity and group velocity dispersion curves while using the general corrosion problem as an example. We first derive a simple and generic wave excitability function based on the theory of normal mode expansion and the reciprocity theorem. A sensitivity dispersion curve is formulated based on the group velocity dispersion curve. Both excitability and sensitivity dispersion curves are verified with finite element simulations. Finally, a
goodness dispersion curve concept is introduced to evaluate the tradeoffs between multiple mode selection objectives based on the wave velocity, excitability and sensitivity.
Sliding motion and adhesion control through magnetic domaminsAndrea Benassi
Actuation and control of motion in micro mechanical systems are technological challenges, since they are accompanied by mechanical friction and wear, principal and well known sources of device lifetime reduction. In this theoretical work we propose a non-contact motion control technique based on the introduction of a tunable magnetic interaction. The latter is realized by coating two non-touching sliding bodies with ferromagnetic films. The resulting dynamics is determined by shape, size and ordering of magnetic domains arising in the films below the Curie temperature. We demonstrate that the domain behavior can be tailored by acting on handles like ferromagnetic coating preparation, external magnetic fields and the finite distance between the plates. In this way, motion control can be achieved without mechanical contact. Moreover, we discuss how such handles can disclose a variety of sliding regimes. Finally, we propose how to practically implement the proposed model sliding system.
A COMPARATIVE STUDY OF VARIOUS METHODS TO EVALUATE IMPEDANCE FUNCTION FOR SHA...Samirsinh Parmar
Impedance function, Foundation Vibration, dynamic soil-structure interaction, Barkan, Dominguez, Dobry and Gazetas for evaluation of impedance functions for various modes of vibration of shallow foundation
Magnetostatic Surface Waves in a Left Handed / Ferrite/ Metal-Strip-Grating ...ijrap
The dispersion characteristics for magnetostatic surface waves in a left handed ( LHM)/ferrite/ metal-stripgrating structure have been investigated. We found that, the waveguide supports backward TE waves
since both permittivity and magnetic permeability of LHM are negative. We also illustrated the
dependence of wave frequency on the reduced wave number for a grating shielding parameter, g values
restricted by the range 0 ≤ g ≥ 1. It is shown that the grating shielding parameter, g induces
magnetostatic backward shorter waves . The leakage through the grating increases with the wave number.
The shorter backward magnetostatic waves are guided by the thicker waveguide where the best
confinement is achieved .
Stability Of Magnetostatic Surface Waves In A Semiconductor-Ferrite-Left-Hand...ijrap
Recently increasing works have been devoted to study and fabricate new artificial materials called
metamaterials or left handed materials. These materials have unusual behavior as they have
simultaneously both negative permittivity and permeability.
In this paper, we investigate the effect of left handed materials and the conductivity of semiconductor
material on the dispersion characteristics of left-handed-ferrite-semiconductor waveguide structure, and
then we discuss the stability of magnetostatic surface waves in the mentioned three waveguide structures by
perturbation method.
Surface Polaritons in GAAS/ALGAAS/LH Hetrojunction Structure in a High Magnet...ijrap
The surface polaritons (SP) variation in Ga As/ Al Ga As/ LH hetrojunction composition in the presence of
a strong transverse quantized magnetic field is estimated using the quantum Hall effect case. The
dispersion characteristics of the SPs are investigated using the dielectric constants values of the Ga As and
the Alx Ga 1-x As media and the defined thickness, the Alx Ga 1-x As medium. The dispersion behaviours
calculated results are listed for considered cases. It was shown that the frequency values against the wave
vector values are affected in a strong manner by changing thickness, of the Alx
Ga 1-x- As media and by
changing the variation of the dielectric constants of Ga As against the Alx Ga 1-x As. The significance
effects of the use of the left-handed (LH) medium as an upper layer of the proposed composition was
demonstrated; the frequency values are remarkably increased using LH material as an upper layer. It was
noticed that at certain conditions of the LH upper layer composition, similar results have been obtained
such as found by using dielectric upper layer.
The Influence Of Infinite Impedance Flanges On The Electromagnetic Field Of A...IJERA Editor
The problem of analysis of the electromagnetic field behaviour from the open end of the parallel-plate
waveguide with infinite impedance flanges is theoretically investigated. The case with the absence of impedance
flanges is also considered. Furthermore, we take into account particular features of the waveguide edges. The
effects of the impedance flanges and the edge features on the electromagnetic field and the radiation patterns of a
plane waveguide with flanges are demonstrated. The method of moments (MoM) technique which was used to
solve the integral equations is presented along with the numerical results.
Plasmon-Polaritons And Their Use In Optical Sub-Wavelength. Event Of Copper A...ijrap
The work undertaken in this article concerns the description of the propagation modes of an incident
electromagnetic wave of wavelength λ (the visible spectrum) to its interaction with a structure typical metal
/ dielectric. The study of this interaction process is the measurement of features that are four parameters
associated with longitudinal modes propagating interface. A comparative study between two structures
silver and copper has been established. The characteristic parameters whose behavior is studied in the
visible spectrum are the propagation length, and the length of penetration in rural and dielectric material.
The typical structure of Kretschmann-Raether being used for the diagnosis of structure, analytical study
shows that copper can be used as a guide for photonic transmission. The direction of propagation, the
electromagnetic field associated with the interface modes present evanescent spatial coherence with which
the behavior is justified by a study of the near field. For this, we have given some results on the density of
states of plasmonic modes on a copper-air interface.
Plasmon-Polaritons And Their Use In Optical Sub-Wavelength. Event Of Copper A...ijrap
The work undertaken in this article concerns the description of the propagation modes of an incident
electromagnetic wave of wavelength λ (the visible spectrum) to its interaction with a structure typical metal
/ dielectric. The study of this interaction process is the measurement of features that are four parameters
associated with longitudinal modes propagating interface. A comparative study between two structures
silver and copper has been established. The characteristic parameters whose behavior is studied in the
visible spectrum are the propagation length, and the length of penetration in rural and dielectric material.
The typical structure of Kretschmann-Raether being used for the diagnosis of structure, analytical study
shows that copper can be used as a guide for photonic transmission. The direction of propagation, the
electromagnetic field associated with the interface modes present evanescent spatial coherence with which
the behavior is justified by a study of the near field. For this, we have given some results on the density of
states of plasmonic modes on a copper-air interface
Plasmon-Polaritons And Their Use In Optical Sub-Wavelength. Event Of Copper A...ijrap
The work undertaken in this article concerns the description of the propagation modes of an incident
electromagnetic wave of wavelength λ (the visible spectrum) to its interaction with a structure typical metal
/ dielectric. The study of this interaction process is the measurement of features that are four parameters
associated with longitudinal modes propagating interface. A comparative study between two structures
silver and copper has been established. The characteristic parameters whose behavior is studied in the
visible spectrum are the propagation length, and the length of penetration in rural and dielectric material.
The typical structure of Kretschmann-Raether being used for the diagnosis of structure, analytical study
shows that copper can be used as a guide for photonic transmission. The direction of propagation, the
electromagnetic field associated with the interface modes present evanescent spatial coherence with which
the behavior is justified by a study of the near field. For this, we have given some results on the density of
states of plasmonic modes on a copper-air interface.
On the Unification of Physic and the Elimination of Unbound Quantitiesijrap
This paper supports Descartes' idea of a constant quantity of motion, modernized by Leibniz. Unlike Leibniz, the paper emphasizes that the idea is not realized by forms of energy, but by energy itself. It remains constant regardless of the form, type, or speed of motion, even that of light. Through force, energy is only transformed. Here it is proved that force is its derivative. It exists even at rest, representing the object's minimal energy state. With speed, we achieve its multiplication up to the maximum energy state, from which a maximum force is derived from the object. From this point, corresponding to Planck's Length, we find the value of the force wherever we want. Achieving this removes the differences between various natural forces. The new idea eliminates infinite magnitudes. The process allows the laws to transition from simple to complex forms and vice versa, through differentiation-integration. For this paper, this means achieving the Unification Theory.
Gravity Also Redshifts Light – the Missing Phenomenon That Could Resolve Most...ijrap
In this paper I discover that gravity also redshifts light like the velocity of its source does. When light travels towards a supermassive object, its waves (or photons) undergo continuous stretching, thereby shifting towards lower frequencies. Gravity redshifts light irrespective of whether its source is in motion or static with respect to its observer. An equation is derived for gravitational redshift, and a formula for combined redshift is presented by considering both the velocity, and gravity redshifts. Also explained is how frequencies of electromagnetic spectrum continuously downgrade as a light beam of mix frequencies passes towards a black hole. Further, a clear methodology is provided to figure out whether expansion of the universe is accelerating or decelerating, or alternatively, the universe is contracting.
In this paper I present a new theory that explains as to when and how dark energy is created as mass is destroyed. The theory extends Einstein’s mass energy equation to a more generic form in order to make it work even in high gravity conditions. It also explains why dark energy is created. Further, it is proved Einstein’s mass energy equation holds good only when the destroyed mass has no supermassive object in its close vicinity. The relationship between dark energy and dark matter is unveiled. An extended mathematical form of Einstein’s mass energy equation is derived, based on which the conditions leading to dark energy creation are explained. Three new physical parameters called dark energy discriminant, dark energy radius and dark energy boundary are introduced to facilitate easy understanding of the theory. It is explained in detail that an extremely superdense object has two dark energy boundaries, outer and inner. Mass destroyed only between these two boundaries creates dark energy. Dark energy space, the space between the two aforementioned boundaries, shrouds visible matter in obscurity from optical and electromagnetic telescopes. This theory identifies Gargantuan as a superdense black hole currently creating fresh dark energy, which could be the subject of interest for the astronomical research community having access to sophisticated telescopes, and working on dark energy. It also upholds dark energy and denies the existence of dark matter. Dark matter is nothing but the well-known visible matter positioned in dark energy space. An important relationship is derived between a photon’s frequency and its distance from a black hole to demonstrate the effect of gravity on light. Another important fact revealed by this theory is gravity stretches out light, thereby causing redshift, which is unaccounted in the computation of velocities of outer galaxies. Whether the universe is undergoing accelerated or decelerated expansion, or accelerated contraction can precisely be determined only after accounting for the redshift caused by gravity
International Journal on Soft Computing, Artificial Intelligence and Applicat...ijrap
International Journal on Soft Computing, Artificial Intelligence and Applications (IJSCAI)
is an open access peer-reviewed journal that provides an excellent international forum for sharing
knowledge and results in theory, methodology and applications of Artificial Intelligence, Soft
Computing. The Journal looks for significant contributions to all major fields of the Artificial
Intelligence, Soft Computing in theoretical and practical aspects. The aim of the Journal is to
provide a platform to the researchers and practitioners from both academia as well as industry to
meet and share cutting-edge development in the field.
Authors are solicited to contribute to the journal by submitting articles that illustrate research
results, projects, surveying works and industrial experiences that describe significant advances in
the areas of Database management systems.
SOME THEORETICAL ASPECTS OF HYDROGEN DIFFUSION IN BCC METALS AT LOW TEMPERATURESijrap
Purpose of the work is to discuss some theoretical aspects of the diffusion of hydrogen atoms in the crystal
lattice of BCC metals at low temperatures using the methods of statistical thermodynamics. The values of
the statistical model calculations of H diffusion coefficients in α-Fe, V, Ta, Nb, K are in good agreement
with the experimental data. The statistical model can also explain deviations from the Arrhenius equation
at temperatures 300-100 K in α-Fe, V, Nb and K. It was suggested that thermally activated fast tunnelling
transition of hydrogen atoms through the potential barrier at a temperature below 300 K provides an
almost free movement of H atoms in the α-Fe and V lattice at these temperatures. The results show that
quantum-statistical effects play a decisive role in the H diffusion in BCC metals at low temperatures. Using
the statistical model allows for the prediction of the diffusion coefficient for H in BCC metals at low
temperatures, where it’s necessary to consider quantum effects.
MASSIVE PHOTON HYPOTHESIS OPENS DOORS TO NEW FIELDS OF RESEARCHijrap
Mass, an inherent property of matter, is calculated directly for the photon particle from the very classical
principles of the kinetic theory of gases. It is not an end result with no perspective nor other outcome.
Quite the opposite, a single ponderable tiny photon frees the mind of old ways of thinking and opens up
new paths to a broad field of investigation where the very large can then be described and explained by the
very small. This reality of a non-zero mass suddenly shows up in the interpretation of many experiments
which become clear and simple to comprehend. Besides, that same key particle has the potential to unlock
and solve some long lasting major observational issues or enigmas. All this converges upon its
acknowledgement and acceptance.
PHENOMENOLOGICAL METHOD REGARDING A THIRD THEORY OF PHYSICS “THE EVENT:THE TH...ijrap
The quest for a third theory uniting macro-cosmos (relativity) and micro-cosmos (quantum mechanics) has coexisted with the denial of feminine/subjective polarity to masculine/objective. The dismissal of electromagnetism as the tension of opposites in quest of inner/outer unity is sourced in the denial of the feminine qualia -- the negative force field attributed to dark energy/dark matter. However, a conversion philosophy sourced in the hieros gamos and signified by the Mobius strip has formulated an integral consciousness methodology producing quantum objects by means of embracing the shadow haunting contemporary physics. This Self-reflecting process integrating subject/object comprises an ontology of kairos as the “quantum leap.” An interdisciplinary quest to create a phenomenological narrative is disclosed via a holistic apparatus of hermeneutics manifesting image/text of a contemporary grail journey. Reflected in this Third space is the sacred reality of autonomous number unifying polarities of feminine/subjective (quality) and objective/masculine (quantity) as new measurement apparatus for the quantum wave collapse.
3rd International Conference on Integrating Technology in Education (ITE 2022)ijrap
3rd International Conference on Integrating Technology in Education (ITE 2022) This forum also aims to provide a platform for exchanging ideas in new emerging trends that needs more focus and exposure and will attempt to publish proposals that strengthen our goals.
A SPECIAL RELATIONSHIP BETWEEN MATTER, ENERGY, INFORMATION, AND CONSCIOUSNESSijrap
This paper discusses the advantages of describing the universe, or nature, in terms of information and consciousness. Some problems encountered by theoretical physicists in the quest for the theory of everything stem from the limitations of trying to understand everything in terms of matter and energy only. However, if everything, including matter, energy, life, and mental processes, is described in terms of information and consciousness, much progress can be made in the search for the ultimate theory of the universe. As brilliant and successful as physics and chemistry have been over the last two centuries, it is important that nature is not viewed solely in terms of matter and energy. Two additional components are needed to unlock her secrets. While extensive writing exists that describes the connection between matter and energy and their physical basis, little work has been done to learn the special relationship between matter, energy, information, and consciousness.
This paper discusses the advantages of describing the universe, or nature, in terms of information and consciousness. Some problems encountered by theoretical physicists in the quest for the theory of everything stem from the limitations of trying to understand everything in terms of matter and energy only. However, if everything, including matter, energy, life, and mental processes, is described in terms of information and consciousness, much progress can be made in the search for the ultimate theory of the universe. As brilliant and successful as physics and chemistry have been over the last two centuries, it is important that nature is not viewed solely in terms of matter and energy. Two additional components are needed to unlock her secrets. While extensive writing exists that describes the connection between matter and energy and their physical basis, little work has been done to learn the special relationship between matter, energy, information, and
consciousness.
THE CONCEPT OF SPACE AND TIME: AN AFRICAN PERSPECTIVEijrap
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MAGNETOSTATIC SURFACE WAVES IN A LEFT HANDED / FERRITE/ METAL-STRIP-GRATING STRUCTURE
1. International Journal of Recent advances in Physics (IJRAP) Vol.1, No.1, August 2012
1
MAGNETOSTATIC SURFACE WAVES IN A LEFT
HANDED / FERRITE/ METAL-STRIP-GRATING
STRUCTURE
H. M. MOUSA
1
AND M. M. SHABAT
2
1
Physics Department, Al Azhar University, Gaza, Gaza Strip,
Palestinian Authority
2
Physics Department, Islamic University, Gaza , P.O.Box
108, Gaza Strip, Palestinian Authority,
e-mail: shabat@mail.iugaza.edu.ps
ABSTRACT
The dispersion characteristics for magnetostatic surface waves in a left handed ( LHM)/ferrite/ metal-strip-
grating structure have been investigated. We found that, the waveguide supports backward TE waves
since both permittivity and magnetic permeability of LHM are negative. We also illustrated the
dependence of wave frequency on the reduced wave number for a grating shielding parameter, g values
restricted by the range 10 ≥≤ g . It is shown that the grating shielding parameter, g induces
magnetostatic backward shorter waves . The leakage through the grating increases with the wave number.
The shorter backward magnetostatic waves are guided by the thicker waveguide where the best
confinement is achieved .
KEYWORDS:
Left handed material, , Magnetostatic waves, metal-strip-grating, Wave-guides, Ferrite..
1. INTRODUCTION
Magnetostatic waves, whose wave number lies between those of electromagnetic waves and
exchange spin waves, propagate in a magnetized ferromagnetic medium due to dipole- dipole
interaction. Since the propagation characteristics of magnetostatic waves depend on the shape of
the medium, many theoretical analysis for an infinite plate, an infinite circular rod[ 1,2 ] etc. had
been reported. The investigation of magnetostatic waves in an infinite plate can be classified into
two groups according to the direction of applied magnetic field. One is the case where the
direction of the applied magnetic field is parallel to the sample surface, and the other is the
perpendicular case where magnetostatic surface waves cannot exist in. In 1961, the magnetostatic
mode in the parallel configuration was analyzed by Damon and Eshbach [2 ]. In this case, two
kinds of magnetostatic modes, volume modes and surface modes, exist. The surface modes have
attracted the attention of many researchers in various waveguide structures containing
semiconductors or dielectrics . They can be applied to nonreciprocal circuit devices and variable
delay lines in microwave integrated circuits due to their nonreciprocal propagation characteristics
and slow group velocity[ 3 ]. Yukawa et.al. had reported the effects of metal on the dispersion
relation of magnetostatic surface waves where the dispersion characteristics are affected by the
2. International Journal of Recent advances in Physics (IJRAP) Vol.1, No.1, August 2012
2
normalized spacing between the sample and the metal [3]. At present, considerable attention is
being given to backward waves whose many properties (such as directivity of propagation as well
as reflection and refraction laws) differ from those of forward waves [4] . Backward
electromagnetic waves can exist in various media, e.g. a left handed materials(LHM) in which
the permittivity and the permeability take negative values in certain frequency range[5-8].
Hamada and Shabat [7] et.al investigated the nonlinear magnetostatic surface waves in a ferrite
left handed waveguide structure. Mousa, Abadlah and Shabat [8] have examined the propagation
characteristics of magnetostatic surface waves in a left-handed material- ferrite -semiconductor
waveguide structures. Backward electromagnetic waves can also exist in composite media
formed by a planar periodic grating of current conducting strips placed in a dielectric matrix
which are called metal strip grating (MSG). These structures have a wide range of applications
in electromagnetic radiating and waveguiding devices such as reflection and transmission filters
and laser output couplers[ 9 ]. Zubkov et.al. studied the dispersion of magnetostatic surface
waves in a ferrite/ dielectric / metal –strip –grating structure. They found that, the leakage of the
wave field through the grating increases with the wave number. Consequently, the slop of the
dispersion curve in the region of backward magnetostatic waves is higher than the slope of this
curve corresponding to a ferrite/ dielectric / metal structure[ 10,11] as a result of the dependence
of the grating shielding parameter on the wave number [4]. The investigation of peculiarities of
wave processes in periodic gratings comprising left handed materials(LHM) is of considerable
interest for the development of new physical principles of electromagnetic waves generation,
amplifying and transmission[12]. In this analysis, a theoretical study of the dispersion properties
of magnetostatic surface waves guided by an optical structure is presented. This structure
consists of a ferrite thin film sandwiched between (LHM) cover and metal –strip –grating
substrate . hε and hµ are electric permittivity and magnetic permeability of LHM respectively
2. DERIVATION OF THE DISPERSION RELATION:
The structure geometry of the problem considered here is shown in Fig.(1). The structure consists
of the ferrite film(YIG) , which occupies the region 0≤≤− xd bounded by LHM cover of the
space 0≥x , and the metal –strip –grating substrate of the space dx −≤ . The magnetic field
0H is applied in the plane of the structure and is parallel to Oz axis.
Grating , g
ferrite fµ
LHM hh µε
Fig.(1) Magnetostatic surface waves waveguide composed of grating
and LHM Layered structure.
x
-d
0
w
b
b
y
3. International Journal of Recent advances in Physics (IJRAP) Vol.1, No.1, August 2012
3
We present the dispersion equation for magnetostatic surface waves propagating in the y direction
with a propagation wave constant in the form exp )]2([ ftkyi π− , where k is the propagation
constant, and f is the operating frequency. The magnetic permeability tensor of the
gyromagnetic ferrite film is given by[2,13,14] :
−=
100
0
0
)( µν
νµ
ωµ i
i
f
Where 122122
)(,)(1 −−
Ω−ΩΩ=Ω−ΩΩ+= HHH νµ . The tensors are called the usual Polder
tensor elements, with 1
00 )4( −
=Ω MHH π and 1
0 )4( −
=Ω Mπγω
0H is the applied magnetic field, 0M is the dc saturation magnetization and γ is the
gyromagnetic ratio for an electron. In order to quantitatively express the partial leakage of the
field, let us introduce a grating shielding parameter, g , such that 10 ≥≤ g [ 5]. The grating,
which is considered infinitely thin, is formed from straight metal strips that are parallel to the
direction of 0H . The grating spacing is b and the window width is w . The value of g = 0
corresponds to completely open slots when the strip width is zero and w =b . The structure
becomes an LHM/ ferrite/vacuum. The value of g =1 corresponds to completely closed slots
when the strip width is equal to grating spacingb and w =0, the grating becomes a completely
shielding. The structure becomes an LHM/ ferrite/metal. The intermediate values of parameter
g correspond to a grating with a certain value of ratio 1−
wb .
From Maxwell's equations we can obtain electric and magnetic field components in three regions
2.1 In grating ( dx −≤ )
01 =∇ Hx
rv
(1a)
0. 1 =∇ b
rr
(1b)
Where 1b
r
is the magnetic induction.
The magnetic potential 1ψ exist and satisfies 11 ψ∇−=
rr
H . (1c)
Substituting eq.(1c) into eq. (1b), 1ψ satisfies the following equation
01
2
2
1
2
2
1
2
2
1
2
=−
∂
∂
=
∂
∂
+
∂
∂
ψ
ψψψ
k
xyx
(2)
The solution is written as:
)(
11
1
)1( tykixk
eeBg ω
ψ −
−= (3)
4. International Journal of Recent advances in Physics (IJRAP) Vol.1, No.1, August 2012
4
Substituting eq.(3) into eq. (2), one gets:
22
1 kk =
The magnetic field components are calculated using 11 ψ∇−=
rr
H and written as:
xk
x ekBg
x
H 1
1
1 )1( −−=
∂
∂
−=
ψ )( tyki
e ω−
(4a)
And
xk
y ekBgi
x
H 1
1
1 )1( −−=
∂
∂
−=
ψ )( tyki
e ω−
(4b)
2.2 In ferrite ( 0≤≤− xd )
02 =∇ Hx
rv
(5a)
0. 2 =∇ b
rr
(5b)
The magnetic induction [ ] 202 Hb f
rr
µµ=
Magnetic potential can be defined in this region too and written as:
)(
222 )( 22 tykixkxk
eeBeAg ω
ψ −−
+= (6a)
The magnetic potential 2ψ satisfies 22 ψ∇−=
rr
H . (6b)
Substituting eq.(6b) into eq. (5b), one obtains:
02
2
2
2
2
2
2
2
2
2
2
=−
∂
∂
=
∂
∂
+
∂
∂
ψ
ψψψ
k
xyx
(6c)
Substituting eq.(6a) into eq. (6c), one gets:
22
2 kk =
Each field component is obtained as :
)(
22
2
2 )( tykixkxk
x eeBeAkg
x
H ωψ −−
−−=
∂
∂
−= (7a)
And
)(
22
2
2 )( tykixkxk
y eeBeAgki
y
H ωψ −−
+−=
∂
∂
−= (7b)
5. International Journal of Recent advances in Physics (IJRAP) Vol.1, No.1, August 2012
5
02 µ=xb
−
0100
0
0
2
2
Y
x
H
H
i
i
µν
νµ
(7c)
Substituting eq.(7a) and eq. (7b) into eq.(7c) we get:
)(
2202 )])()([ tykixkxk
x eeBseAskgb ω
νµµνµ −−
++−=
Where s takes +1 or -1 according as the static magnetic field is applied in +z or –z direction
respectively.
2.3 In LHM ( 0≥x )
303 EiHx h
rrv
εεω−=∇ (8a)
303 HiEx h
rrv
µωµ=∇ (8b)
Where,
2
0
2
2
2
2
1)(,1)(
ωω
ω
ωµ
ω
ω
ωε
−
−=−=
F
h
p
h
with plasma frequency pω and resonance frequency 0ω .
The wave equation can be found easily from the Maxwell's equations as :
0)( 00
22
2
3
2
=−−
∂
∂
zhh
z
Ek
x
E
µεεµω (9a)
The exact solution of Eq(4) has the form
( ) xk
z eAxE 3
33
−
= )( tyki
e ω−
, (9b)
By eqs.(8b) and (9b) we get the magnetic field as follow
h
x
k
H
µωµ0
3
−
= xk
eA 3
3
− )( tyki
e ω−
,
h
y
ik
H
µωµ0
3
3 = xk
eA 3
3
− )( tyki
e ω−
where hhkk µεεµω 00
22
3 −= is decay constant of the waves in LH cover.
3A is an amplitude coefficient which can be determined by the boundary conditions
6. International Journal of Recent advances in Physics (IJRAP) Vol.1, No.1, August 2012
6
Matching the field components yH and xb at the boundary 0=x , but at the surface of the
grating =x d− , the wave field is not completely shielded by the grating and partially leaks
through it into free space so the boundary conditions at =x d− are:
(1+g) 1yH = 2yH and 21 xx bb = , we have the following equations for 2A and 2B
,
+++−++
+−−−
−− 2
2
11
)])(1(1[)])(1(1[
)(1)(1
B
A
esgesg
ss
dkdk
µνµν
µνγµνγ
= 0
This system admits a non trivial solution only in case its determinant is zero, the
dispersion equation is
[ ][ ]
[ ][ ]))(1(1)(1
))(1(1)(1
1
12
νµµνγ
µννµγ
sgs
sgs
e dk
+++−−
−+++−
=−
(10)
The grating shielding parameter, g , appears in dispersion relation (10), it is supposed that g is
related to wave number k as[5]
1
1
0)(
−∞
=
+= ∑ n
n
n kAAkg (11)
Where 0A and nA are unknown coefficients that can be found from electro-dynamic
calculations[4]. Let us consider the changes that dispersion curves undergo as parameters 0A and
nA are varied. Parameter 0A is determined by the spacing of the grating. When 0A =2 , the slot
width is equal to the strip width and to half the spacing of the grating: bw 5.0= . The problem is
simplified by restricting our analysis to use of only the following parameter pairs: 0A =2 and one
of coefficients nA .
3. NUMERICAL RESULTS AND DISCUSSION:
In this paper, the numerical calculations for LHM/ferrite/grating waveguide are taken with the
following parameters: GHzGHzp 42/,102/ 0 == πωπω and 56.0=F [3],
000 ,17504 MHGsM ππ == Oe [4,14 ]. The frequency range in which both hε and hµ are
negative is from 4 to 6 GHz. In this range, and at a definite thickness such as md µ30= , the
solution for TE wave frequency f as a function of reduced wave number, kd is found by solving
Eq.(10) . Figure (2a) displays the TE wave frequency )2/( πω=f versus the reduced wave
number kd for two values of a grating shielding parameter, g , (i.e., for curves ("1", "2" )
7. International Journal of Recent advances in Physics (IJRAP) Vol.1, No.1, August 2012
7
where g increases to the values (0, 1)the higher frequency value is respectively observed in (4.66,
5.02GHz). This means that when g =0, the structure becomes LHM/ferrite/vacuum and when
g =1, the structure becomes LHM/ferrite/metal. The metal affects the longer waves more strongly
than the shorter waves. As a result, the metal behaves as a shielding for the longer waves and no
wave leakage is occurred where the wave frequency is maximum. The effect of LHM layer is also
observed through the negative values of the kd (-0.5 to -3) where the magnetostatic TE waves are
all backward travelling. Figure (2b) describes the dispersion curves, )(kdf for g dependence on
the wave number k . Values of g are restricted by the range 10 fp g . In this case, the structure
is LHM/ferrite/grating. According to Eq.(11), the curves ("1", "2", "3" and "4") are obtained at
0A =2 and one of coefficients nA as: 0A =2 and 210
2 10 mA −
= , 220
4 10 mA −
= , 230
6 10 mA −
=
and 240
8 10 mA −
= respectively. The dispersion curves are different from that in Fig.(2a). By
decreasing n to the values of (8, 6, 4 and 2), the dispersion curves of the magnetostatic backward
waves are shifted to increasing kd of values (-4.2, -4.8, -6 and -11.4) with decreasing slop
respectively. It is obvious that these waves are shorter than the waves affected by the metal and
with lower frequencies than them(about 4.42 GHz). This means that, the leakage through the
grating increases with the wave number. This is the same that obtained by Zubkov et.al.[ 4 ].
They found that, the leakage of the wave field through the grating increases with the wave
number in the region of backward magnetostatic waves existing in a ferrite/ dielectric / metal –
strip –grating structure .Figure (3) illustrates the effect of the thickness of the ferrite layer on the
dispersion curves, )(kdf for 220
4 10 mA −
= . As the thickness d increases to the
values )30,25,20( mµ , the curves are shifted to increasing kd of values (-3.9, -4.9, and -5.9)
where the shorter backward magnetostatic waves are guided by the thicker waveguide . As
noticed in Fig.4, the dispersion curves, )(kdf for 220
4 10 mA −
= and ( s=1, -1) are plotted for
different magnetic field values. At s=1, increasing of the magnetic field 0H to the values
of(1750/4, 1770/4, 1800/4 Oe) will guide the shorter waves while at s=-1, the longer waves of
higher frequency are observed.
Figure( 2a,b). Dispersion curves of magnetostatic TE waves for (a) (1) g = 0, (2) g = 1. (b)
0A =2 and 210
2 10 mA −
= , 220
4 10 mA −
= , 230
6 10 mA −
= and 240
8 10 mA −
= (curves 1-5,
respectively). The curves are labeled with values of
GHzGHzp 42/,102/ 0 == πωπω , OeH )4/1750(0 = , md µ30= , s =1 ,
and 0,0 pp hh µε .
8. International Journal of Recent advances in Physics (IJRAP) Vol.1, No.1, August 2012
8
Figure 3. Dispersion curves of magnetostatic TE waves for (1) md µ30= , (2) md µ25= and
(3) = md µ20= (b). The curves are labeled with values of 0A =2 and 220
4 10 mA −
=
, GHzGHzp 42/,102/ 0 == πωπω , OeH )4/1750(0 = , s =1 .
Figure 4. Dispersion curves of magnetostatic TE waves for (1) OeH )4/1800(0 = , (2)
OeH )4/1770(0 = and (3) = OeH )4/1750(0 = . The curves are labeled with values of 0A =2
and 220
4 10 mA −
= , GHzGHzp 42/,102/ 0 == πωπω , md µ30= .
9. International Journal of Recent advances in Physics (IJRAP) Vol.1, No.1, August 2012
9
4.CONCLUSIONS:
The dispersion of the magnetostatic surface waves existing in an LHM/ferrite/grating structure
has been investigated. It is shown that LHM induces the waves to be backward in all dispersion
regions, the dependence of the grating shielding parameter on the wave number induces the
existence of shorter waves which have more leakage through the grating. Consequently, their
frequency is lower than that of the waves existing in an LHM/ferrite/metal structure. These
characteristics properties could be used in design future applications in microwave technology.
ACKNOWLEDGEMENTS:
One of the authors (M .M. Shabat) acknowledges financial support from the Alexander von
Humboldt, Germany for a study visit to Germany, and the hospitality of Prof. H. Roskos, at the
Wolfgang Goethe-Universität, Frankfurt.
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[3] T. Yukawa, J. Yamada, K . Abe, J. Ikenoue, (1977) , Japanese J. App. Phys., Vol.18, No.12, pp.
2187-2196.
[4] V. I. Zubkov. and V. I. Shcheglov, (2006), J. Comm.Tech.and Elect.51, No. 3, 311.
[5] V. G Veselago, (1967), Sov. Phys.:Usp. 10, 509.
[6] I.V Shadrivov, A. A. Sukhorakov, Y.S. Kivshar, (2004), Phys. Rev. E.69, 016617 .
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