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Electro magnetic mode theory

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Page 1: Electro magnetic mode theory
Page 2: Electro magnetic mode theory

INSTRUCTOR:SIR SAQLAIN

SHAHPresented By:

Name Registration No.UMAIZ AHMAD FA14-BEE-003

YASIR ZULFIQAR FA14-BEE-015

Page 3: Electro magnetic mode theory

Electromagnetic mode Theory for Optical Propagation:

Light is an electromagnetic phenomenon described by the same theoreticalPrinciples that govern all forms of electromagnetic radiation. Maxwell’sequations are in the heart of electromagnetic theory & is fully successful inproviding treatment of light propagation. Electromagnetic optics provides themost complete treatment of light phenomena in the context of classical optics.

Electromagnetic radiation propagates in the form of two mutually coupled vector waves, an electric field wave & a magnetic field wave. Both are vector functions of position & time. In a source-free media, such as free space, these electric & magnetic fieldssatisfy the following partial differential equations, known as Maxwell’s equations:

Page 4: Electro magnetic mode theory

00

BD

tHE

tEH

• In Maxwell’s equations, E is the electric field expressed in [V/m], H is the magnetic field expressed in [A/m].

ty permeabili Magnetic :[H/m] ty permittivi Electric :[F/m]

operation curl is :operation divergence is :

Page 5: Electro magnetic mode theory

The solution of Maxwell’s equations in free space, through the wave equation, can be easily obtained for monochromatic electromagnetic wave. All electric & magnetic fields are harmonic functions of time of the same frequency. Electric & magnetic fields are perpendicular to each other & both perpendicular to the direction of propagation, k, known as transverse wave (TEM). E, H & k form a set of orthogonal vectors.

Electromagnetic Plane wave in Free SpaceEx

z

Direction of Propagation

By

z

x

y

k

An electromagnetic wave is a travelling wave which has timevarying electric and magnetic fields which are perpendicular to eachother and the direction of propagation, z.

Page 6: Electro magnetic mode theory

Taking curl of Maxwell's equation

Page 7: Electro magnetic mode theory

Modes in Planar Guide:

Page 8: Electro magnetic mode theory
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Group Velocity:

Page 10: Electro magnetic mode theory

Goos–Haenchen shift: