Cylindrical Waveguide on Ferrite Substrate Controlled by Externally Applied Magnetic Field

This paper presents an extension of the formulation of wave propagation in transverse electric (TE) and transverse magnetic (TM) modes for the case of metallic cylindrical waveguides filled with longitudinally magnetized ferrite. The higher order modes were exploited. We externally controlled the cut-off frequency through the application of DC magnetic fields. The numerical results of dispersion diagrams for TE and TM modes were obtained and analyzed. We analyzed a waveguide antenna filled with partially magnetized ferrite using the mode matching (MM) technique based on the TE and TM modes. By using modal analysis, our approach considerably reduced the computation time compared to HFSS. Ferrites are important for various industrial applications, such as circulators, isolators, antennas and filters.

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Rigorous study of propagation in metallic circular waveguide filled with anisotropic metamaterial

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078716000970 ◽

2017 ◽

Vol 9 (4) ◽

pp. 805-813 ◽

Cited By ~ 1

Author(s):

Hedi Sakli ◽

Mohamed Yahia ◽

Wyssem Fathallah ◽

Jun Wu Tao ◽

Taoufik Aguili

Keyword(s):

Computation Time ◽

Circular Waveguide ◽

Transverse Magnetic ◽

Higher Order Modes ◽

Anisotropic Metamaterials ◽

Matching Technique ◽

Theoretical Predictions ◽

Rigorous Study ◽

Circular Waveguides ◽

Anisotropic Metamaterial

This paper presents an extension of the formulation of wave propagation in transverse electric (TE) and transverse magnetic (TM) modes in the case of metallic circular waveguides filled with anisotropic metamaterials. The determined higher-order modes have been analyzed and exploited to the design of filters. Among the particularities of anisotropic material, the backward waves can propagate below the cut-off frequency. The numerical results for TE and TM modes have been compared with theoretical predictions. Good agreements were obtained. We analyzed a periodic structure containing waveguides filled with anisotropic metamaterial using the mode-matching technique. By using modal analysis, our approach reduced considerably the computation time compared to HFSS.

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Alternative derivations for the fields inside a waveguide

Journal of Electrical Engineering ◽

10.2478/jee-2021-0018 ◽

2021 ◽

Vol 72 (2) ◽

pp. 129-131

Author(s):

Raghavendra G. Kulkarni

Keyword(s):

Magnetic Field ◽

Wave Equation ◽

Electric Field ◽

Longitudinal Magnetic Field ◽

Transverse Electric ◽

Transverse Magnetic ◽

Longitudinal Electric Field ◽

Microwave Engineering ◽

Introductory Textbooks ◽

Helmholtz Wave Equation

Abstract Generally, the longitudinal magnetic field of the transverse electric (TE) wave inside a waveguide is obtained by solving the corresponding Helmholtz wave equation, which further leads to the derivation of the remaining fields. In this paper, we provide an alternative way to obtain this longitudinal magnetic field by making use of one of the Maxwell’s equations instead of directly relying on the Helmholtz wave equation. The longitudinal electric field of the transverse magnetic (TM) wave inside a waveguide can also be derived in a similar fashion. These derivations, which are different from those found in the introductory textbooks on microwave engineering, make the study of waveguides more interesting.

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Realization of tunable TE/TM wave splitter with one-dimensional plasma dielectric photonic crystal

International Journal of Modern Physics B ◽

10.1142/s0217979218502533 ◽

2018 ◽

Vol 32 (23) ◽

pp. 1850253 ◽

Cited By ~ 2

Author(s):

K. F. Shen ◽

B. Guo

Keyword(s):

Magnetic Field ◽

Photonic Crystal ◽

Transverse Electric ◽

Incident Angle ◽

Transverse Magnetic ◽

Dielectric Medium ◽

Frequency Region ◽

The Other ◽

Reflection And Transmission ◽

One Dimensional

A tunable transverse electric (TE) and transverse magnetic (TM) wave splitter using one-dimensional plasma dielectric photonic crystal which consists of plasma arranged periodically in a host dielectric medium is proposed. We performed a detailed study to explore the phenomena of reflection and transmission that occurs on obliquely incident electromagnetic wave propagating in the proposed plasma dielectric photonic crystal. We exactly calculated the transmittance based on the transfer matrix method. We find that if the parameters are selected appropriately, in the TE-stop or TM-stop frequency region, the other polarized component TM or TE wave is totally transmitted. The results also show that the dielectric constant, plasma thickness, incident angle and the applied magnetic field have significantly changed the properties of the TE/TM wave splitter. Moreover, the external magnetic field can be used as a kind of tunable method once the splitter is fabricated. Parameter dependence of the effects for the TE/TM wave splitter is calculated and discussed.

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Effects of Birefringence in Ordered GaInP/AlGaInP Lasers

MRS Proceedings ◽

10.1557/proc-417-97 ◽

1995 ◽

Vol 417 ◽

Cited By ~ 1

Author(s):

A. Moritz ◽

R. Wirth ◽

C. Geng ◽

F. Scholz ◽

A. Hangleiter

Keyword(s):

Transverse Electric ◽

Laser Light ◽

Mode Conversion ◽

Growth Conditions ◽

Transverse Magnetic ◽

Optical Birefringence ◽

Chemical Ordering ◽

Te And Tm Modes ◽

Ternary Semiconductors ◽

Partial Chemical

AbstractTernary semiconductors like GaInP under certain growth conditions exhibit a (partial) chemical ordering in form of a superlattice of alternate Ga-rich and In-rich planes in (111) direction. We have performed measurements of the polarization properties of light propagating in ordered GaInP/AlGaInP quantum well waveguide structures with various amounts of strain and observed a mode conversion between transverse electric (TE) and transverse magnetic (TM) modes for light propagating along (110). Lasers built of ordered material with the cavity in this direction show a distorted polarization of the laser light which depends on ordering and strain. We show that these effects are caused by an optical birefringence due to the reduced symmetry of the ordered material which leads to a coupling of the TE and TM modes. Only a new linear combination of TE and TM modes, the “super-modes”, can propagate in the waveguide without change. Within this simple model the polarization behavior of the light in the waveguide and in lasers can be explained very well.

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Effect of Uniform Magnetic Field on Melting at Various Rayleigh Numbers

Emerging Science Journal ◽

10.28991/esj-2019-01189 ◽

2019 ◽

Vol 3 (4) ◽

pp. 263-273 ◽

Cited By ~ 1

Author(s):

Sumer Bharat Dirbude ◽

Vivek Kumar Maurya

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Natural Convection ◽

Heat Transfer Rate ◽

Transfer Rate ◽

Turbine Blades ◽

Transverse Magnetic ◽

Melting Rate ◽

Industrial Applications ◽

Rayleigh Numbers

Melting phenomena occurs in various industrial applications, such as metal castings of turbine blades, environmental engineering, PCM-based thermal storage devices, etc. During the design of these devices, they are designed for efficient heat transfer rate. To improve the heat transfer rate, understanding of the important flow processes during the melting (and solidification) is necessary. An objective of the present work is to study the effect of natural convection and magnetic field on interface morphology and thereby on melting rate. In this work, therefore, an effect of uniform transverse magnetic field on the melting inside a cavity, filled initially with solid gallium, at various Rayleigh numbers (Ra=3×105, 6×105, and 9×105) is presented. A 2D unsteady numerical simulation, with the enthalpy-porosity formulation, is performed using ANSYS-Fluent. The magnetic field is characterized by the Hartmann number (Ha) and the results are shown for the Ha = 0, 30 and 50. The horizontal walls of the cavity are considered insulated and vertical walls are respectively considered hot and cold. It is observed that the role of natural convection during the melting is significant on the temperature distribution and solid-liquid interface. The increased magnetic field (Ha = 30 and 50) found to have a suppressing effect on the dominance of natural convection at all Rayleigh numbers (Ra=3×105, 6×105, and 9×105).

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Radio Measurements of Coronal Magnetic Fields

International Astronomical Union Colloquium ◽

10.1017/s0252921100024933 ◽

1994 ◽

Vol 144 ◽

pp. 21-28 ◽

Cited By ~ 4

Author(s):

G. B. Gelfreikh

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Solar Corona ◽

Active Regions ◽

High Sensitivity ◽

Coronal Magnetic Field ◽

Transverse Magnetic ◽

Radio Sources ◽

Radio Waves ◽

Solar Active Regions

AbstractA review of methods of measuring magnetic fields in the solar corona using spectral-polarization observations at microwaves with high spatial resolution is presented. The methods are based on the theory of thermal bremsstrahlung, thermal cyclotron emission, propagation of radio waves in quasi-transverse magnetic field and Faraday rotation of the plane of polarization. The most explicit program of measurements of magnetic fields in the atmosphere of solar active regions has been carried out using radio observations performed on the large reflector radio telescope of the Russian Academy of Sciences — RATAN-600. This proved possible due to good wavelength coverage, multichannel spectrographs observations and high sensitivity to polarization of the instrument. Besides direct measurements of the strength of the magnetic fields in some cases the peculiar parameters of radio sources, such as very steep spectra and high brightness temperatures provide some information on a very complicated local structure of the coronal magnetic field. Of special interest are the results found from combined RATAN-600 and large antennas of aperture synthesis (VLA and WSRT), the latter giving more detailed information on twodimensional structure of radio sources. The bulk of the data obtained allows us to investigate themagnetospheresof the solar active regions as the space in the solar corona where the structures and physical processes are controlled both by the photospheric/underphotospheric currents and surrounding “quiet” corona.

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Single-peak-regulation and wide-angle dual-band metamaterial absorber based on hollow-cross and solid-cross resonators

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200145 ◽

2020 ◽

Vol 91 (3) ◽

pp. 30901

Author(s):

Yibo Tang ◽

Longhui He ◽

Jianming Xu ◽

Hailang He ◽

Yuhan Li ◽

...

Keyword(s):

Transverse Electric ◽

Surface Current ◽

Dielectric Substrate ◽

Transverse Magnetic ◽

Metamaterial Absorber ◽

Absorption Peak ◽

Dual Band ◽

Single Peak ◽

Wide Angle ◽

Surface Current Density

A dual-band microwave metamaterial absorber with single-peak regulation and wide-angle absorption has been proposed and illustrated. The designed metamaterial absorber is consisted of hollow-cross resonators, solid-cross resonators, dielectric substrate and metallic background plane. Strong absorption peak coefficients of 99.92% and 99.55% are achieved at 8.42 and 11.31 GHz, respectively, which is basically consistent with the experimental results. Surface current density and changing material properties are employed to illustrate the absorptive mechanism. More importantly, the proposed dual-band metamaterial absorber has the adjustable property of single absorption peak and could operate well at wide incidence angles for both transverse electric (TE) and transverse magnetic (TM) waves. Research results could provide and enrich instructive guidances for realizing a single-peak-regulation and wide-angle dual-band metamaterial absorber.

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