Tunable Materials With Applications in Antennas and Microwaves

Description

Tunable Materials with Applications in Antennas and Microwaves is a stimulating topic in these modern times. With the explosion of the new generation of the wireless world, greater emphasis than ever before is being placed on the analysis and applications of modern materials. This book describes the characteristics of Ferrites and Ferroelectrics and introduces the reader to Multiferroics. Represents, in a simple manner, the solid state physics and explains the permittivity and permeability tensor characteristics for the tunable materials of infinite and finite dimensions.Gives the applications of tunable materials in resonators, filters, microstrips, striplines, antennas, phase shifters, capacitors, varactors, and frequency selective surfaces.Describes in detail the mathematical analysis for spin and magnetostatic waves for infinite medium, thin slab films, and finite circular discs. The analysis contains original work, which the reader may extend in the future.Provides multiferroics, which are ferrite and ferroelectric composites. Multiferroics are very promising tunable materials which are believed will offer many applications in the near future.Contains the planar transmission lines with analytic formulas for multilayer microstrips, transmission lines, and waveguides with isotropic as well as anisotropic dielectric and magnetic materials. Also, gives the formulas to analyze the layered category of transmission lines with multiferroics. This book is intended for antenna and microwave engineers as well as for graduate students of Materials Science and Engineering, Electrical & Computer Engineering, and Physics Departments. List of Figures List of Tables Preface Acknowledgments Ferrites and Ferroelectrics Tunable Electromagnetic Materials Overview of the Evolution of Ferrites Ferroelectrics Bulk Ferroelectrics Thin Film Ferroelectrics Ferrite–Ferroelectric Films Tunable Frequency Selective Surfaces (FSSs) References Tunable Materials–Characteristics and Constitutive Parameters Introduction Microwave Ferrites Historical Evolution Unique Ferrite Features Integration of Microwave Magnetic Basic Properties of Magnetic Materials Electron Magnetic Moment—Bohr Magneton Properties and Types of Magnetic Materials Ferrimagnetics: Ferrite Materials and Magnetic Garnets Spinnel Ferrites Hexagonal Ferrites or Hexaferrites–Permanent Magnetic Ferrites Magnetic Garnets Ferrite Films Garnet Monocrystallized Films Polycrystalline Ferrite Films Ferrite Films and MMIC Combatibility Ferrite Constitutive Relations Magnetization Equations Permeability Tensor Axial Magnetization in Cylindrical Coordinates Circumferential Magnetization in Cylindrical Coordinates Magnetization at an Arbitrary Direction in Cartesian Coordinates Permeability Tensor: Taking Losses into Account Dielectric Properties of Ferrites Electronic Polarizability (_e) Ionic or Atomic Polarizability (_i) Permanent Dipole Polarizility (_d) Space Charge Polarizability (_s) Dielectric Losses Conduction Mechanism in Ferrites and Garnets Magnetic Losses Ferroelctric Properties Electric Polarization–Permittivity Ferroelectricity Hysteresis Loop Ferroelectric Materials—Perovskites The Perovskite Crystal Structure Ferroelectricity as a Result of Crystallic Asymmetry Paraelectric Phase Quantum or Incipient Ferroelectric Perovskite Superlattices Conventional Ferroelectrics—Temperature and DC Bias Dependence Superconductor Perovskites Ferroelectric Layers and Electrode Interfaces Hysteresis Loop of Ferroelectrics Theory of the Ferroelectric Dielectric Response Ferroelectric Tunability Ferroelectric Microwave Losses Intrinsic Losses Extrinsic Losses Losses Due to Charged Defects Losses of Local Polar Regions References Finite Ferrite Samples Demagnitization Factors and Ferrite Samples Spin Waves and Magnetostatic Waves Low– vs. High–Order Spin Waves Magnetostatic Modes Spin–Wave Spectrum Manifold Exchange–Field Interaction Anisotropy Energy Magnetization Equation for Spin Waves Spin Waves as Magnons Spin Waves in an Infinite Medium Spin Waves Including Dipolar Interactions Spin–Waves Accounting for Dipole–Dipole Interaction Spin–Wave Manifold Preliminaries to Spin–Wave Excitation Spin Waves in a Finite Sample Magnetostatic Waves Susceptibility and Characteristic Equation–Uniform Mode The Magnetostatic Equation of a Uniformly Biased Specimen Magnetostatic Modes in an Infinite Medium Magnetostatic Manifold Magnetostatic Modes of an Infinitely Extending Thin Slab Film Phase and Group Velocities of MSFVW Longitudinally Magnetized Infinitely Extending Thin Slabs Magnetostatic Volume Modes (1+X) 0 MSSW Propagating in the y–Direction (k_z=0) Non–Reciprocal Surface–Wave Modes Polarization of Magnetostatic Waves Polarization of MSSW Modes Graphic Representation of Magnetostatic Waves Magnetostatic Modes in an Infinite Circular Disk-Perpendicular Magnetization Finite Ferrite Disks Finite Cylindrically Symmetric Samples–Rods Faraday Rotation–Circular Polarization (CP) Magnetostatic Waves on Multilayer and Grounded Structures Grounded Ferrite Slab Magnetostatic Volume Modes: (1+X) 0 Surface Waves Propagating Only in the –Direction (k_z=0) Grounded Dielectric–Ferrite Layers Magnetostatic Volume Modes (1+X) 0 Surface Waves Propagating Only in the –Direction (k_z=0) Magnetostatic Modes of a Finite Width Slab Surface Modes of Finite Width Slab (-w/2 z w/2) Volume Modes of a Slab Finite in the z–Dimension Volume Modes of a Slab Finite in y–Dimension Transversely Biased Grounded Dielectric–Ferrite Layers Shielded Dielectric–Ferrite Layers Transversely Magnetized Shielded Dielectric–Ferrite Layers (MSFVW) Longitudinally Magnetized Shielded Dielectric Ferrite Layers Magnetostatic Volume Modes Magnetostatic Surface Modes (1+X) > 0 Magnetized and Spin Waves in Ferrite Slab with Losses Magnetostatic Wave Spectrum in the Presence of Losses References Multiferroics: Ferrite–Ferroelectric Composites Introduction Multiferroic Properties Topologies—Connectivity at Two–Phase Composites Multiferroics Constitutive Relations References Planar Transmission Lines Introduction Multilayer Microstrip Lines Three–Layers Microstrip Line Multiple Dielectric Layer Microstrip Line Frequency Dispersion of Multilayer Microstrip Lines Equivalent Single–Layer Microstrip (SLR) Characteristic Impedance vs. Frequency, Z_0(f) Dielectric Losses Coplanar Transmission Lines Multilayer Coplanar Waveguide (CPW) Quasi–Static Approximation Symmetric Multilayer Coplanar Waveguides (w_1 = w_2 = w) Single–Layer CPW Multilayer CPW with Finite Ground Planes Characteristic Impedance Multilayer Coplanar Strips Microstrip Line on a Single Magnetic Substrate Microstrip on a Single Anisotropic Dielectric Substrate Microstrip Printed on a Weakly Magnetized Ferrite–Dielectric Substrate Microstrip Lines on Gyrotropic Substrate TEM Duality Principle in Gyrotropic Media References Authors' Biographies Blank Page