Electromagnetic wave propagation in magnetized Ferrites

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ELECTROMAGNETIC WAVE PROPAGATION IN MAGNETEZED FERRI TES

by

N.C,Srivagtava

Thesis submitted to the Indian Institute of Technology,Delhi for the award of the Degree of

DOCTOR OF PHILOSOPHY

Department of Physics

Indian Institute of Technology,Delhi March, 1977

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ACKNOWLEDGEMENT

I wish to express my deep sense of gratitude to Professor M.S.Sodha and Dr. D.P.Tewari for their

valuable guidance, kind encouragement and inspiration throughout the course of this work.

I am also grateful to Professor A.K.Ghatak for useful discussions and encouragement.

It is a pleasure to thank Mr. S.S.Shaxma and

Mr. G. Umesh for the much needed help in the preparation of the present thesis. I am also thankful to my other colleagues in the Electrophysics Group, Delhi for their cooperation.

Sincere thanks are due to Mr. T.N.Gupta for the efficient typing and his help in the preparation of this thesis.

,

(N. C. Srivastava)

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CONTENTS

CHAPTER Page

PREFACE 1

PART - I

ETRZTROMAGNETIC WAVE PROPAGATION IN MAGNETIZED PLANAR FERRITE

1.1 Introduction 18

1.2 The Coordinate Transformation 21 1.3 Plane Wave Propagation 27 1.4 Propagating and Non-propagating Regions

31 1.5

Polarization of Modes

38

1.6 Conclusions 41

REFERENCES

42

II REFLECTION OF ELECTROMAGNETIC WAVES FROM PLANAR FERRITE

2.1 Introduction

44

2.2

Reflection of Plane Waves 47 a) Reflection & Transmission Coefficients

47

b) The Regions of Ordinary & Total Reflection

52

2.3 Phaseshift on Total Reflection 63

2.4

Reflection from Lossy Ferrite

74 2.5 Summary 84

REFERENCES

85 III

ELECTROMAGNETIC WAVE PROPAGATION IN WAVE GUIDES PARTIALLY LOADED WITH MAGNETIZED PLANAR FERRITE

3.1

Introduction 87

3.2

Theory

89

3.3

Numerical Results and Discussions

95

REFERENCES 10

5

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PART-II

IV PROPAGATION OF SURFACE WAVES THROUGH THE GAP BETWEEN OPPOSITELY MAGNETIZED FERRITE SUBSTRATES

4,1 Introduction 106

4,2 Theory 109

4 Magnetostatic Analysis 109 B) Rigorous Analysis 113 4,3 Numerical Results and Discussions 115

4,4 Conclusions 121

REFERENCES 123

V MAGNETOSTATIC MODES OF A SLAB OF PLANAR FERRITE

5,2 Theory 126

A) Air-Ferrite-Air Strata 128 B) Air-Ferrite-Metal Strata 133

5.3

Numerical Results and Discussions 135

5,4 Conclusions 136

REFERENCES 140

VI ELECTROMAGNETIC WAVE PROPAGATION ALONG CURVED FERRITE SURFACES _

6.2 Theory 142

a) Magnetostatic Solution 142 b) Electromagnetic Solution .145 6,3 Magnetostatic Surface Waves in Curved Slab 147

a) Dispersion Relation 147 b) Special Cases 150 c) General Case 153

6,4 Conclusions 155

REFERENCES 157

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PART - III

VII MODULATION OF ELECTROMAGNETIC WAVES BY TINE DEPENDENT MLGNETICITELDS IN =RITES

7.1 Introduction 158

7.2

7.3

Modulation in Infinite Nedium The rf Magnetization

159

161 7.4 Propagation Across Interfaces: Slab Problem 163 7.5 Numerical Results and Discussions 166

APPENT1X-I 169

REFERENCES 172

REPRINTS AND PREPRINTS BIO DATA