Syllabus (PHYSICS)

Course Type: MAJ-9

Semester: 6

Course Code: BPHSMAJ09C

Course Title: Electromagnetic Theory

(L-P-Tu): 4-2-0

Credit: 6

Practical/Theory: Combined

Course Objective: Electromagnetic Theory

Learning Outcome: Electromagnetic Theory

CC 9: Electromagnetic Theory (6 Credits)

Course Objective:

Theory (4 Credits)

Maxwell Equations: Maxwell’s equations. Displacement Current. Vector and Scalar Potentials. Gauge Transformations: Lorentz and Coulomb Gauge. Boundary Conditions at Interface between Different Media. Wave Equations. Plane Waves in Dielectric Media. Poynting Theorem and Poynting Vector. Electromagnetic (EM) Energy Density. Physical Concept of Electromagnetic Field Energy Density, Momentum Density and Angular Momentum Density. (12 Lectures)

EM Wave Propagation in Unbounded Media: Plane EM waves through vacuum and isotropic dielectric medium, transverse nature of plane EM waves, refractive index and dielectric constant, wave impedance. Propagation through conducting media, relaxation time, skin depth. Wave propagation through dilute plasma, electrical conductivity of ionized gases, plasma frequency, refractive index, skin depth, application to propagation through ionosphere. (9 Lectures)

Dispersion: Equation of motion of an electron in a radiation field : Lorentz theory of dispersion - normal and anomalous; Sellmeier’s and Cauchy’s formulae, absorptive and dispersive mode, half power frequency, band width. (3 Lectures)

EM Wave in Bounded Media: Boundary conditions at a plane interface between two media. Reflection & Refraction of plane waves at plane interface between two dielectric media-Laws of Reflection & Refraction. Fresnel's Formulae for perpendicular & parallel polarization cases, Brewster's law. Reflection & Transmission coefficients. Total internal reflection, evanescent waves. Metallic reflection (normal Incidence) (8 Lectures)

Polarization of Electromagnetic Waves: Description of Linear, Circular and Elliptical Polarization. Propagation of E.M. Waves in Anisotropic Media. Symmetric Nature of Dielectric Tensor. Fresnel’s Formula. Uniaxial and Biaxial Crystals. Light Propagation in Uniaxial Crystal. Double Refraction. Polarization by Double Refraction. Nicol Prism. Ordinary & extraordinary refractive indices. Production & detection of Plane, Circularly and Elliptically Polarized Light. Phase Retardation Plates: Quarter-Wave and Half-Wave Plates. Babinet Compensator and its Uses. Analysis of Polarized Light. (12 Lectures)

Rotatory Polarization: Optical Rotation. Biot’s Laws for Rotatory Polarization. Fresnel’s Theory of optical rotation. Calculation of angle of rotation. Experimental verification of Fresnel’s theory. Specific rotation. Laurent’s half-shade polarimeter. (5 Lectures)

Wave guides: Planar optical wave guides. Planar dielectric wave guide. Condition of continuity at interface. Phase shift on total reflection. Eigenvalue equations. Phase and group velocity of guided waves. Field energy and Power transmission. (8 Lectures)

Optical Fibers: Numerical Aperture. Step and Graded Indices (Definitions Only). Single and Multiple Mode Fibres (Concept and Definition Only). (3 Lectures)

Practical (2 Credits)

List of Practicals (Any four)

1. To verify the law of Malus for plane polarized light.

2. To determine the specific rotation of sugar solution using Polarimeter.

3. To determine the Boltzmann constant using V-I characteristics of PN junction diode.

4. To study the polarization of light by reflection and determine the polarizing angle for air-glass interface.

5. To determine the refractive Index of (1) glass and (2) a liquid by total internal reflection using a Gaussian eyepiece.

6. To verify the Stefan`s law of radiation and to determine Stefan’s constant.

Reading References:

Theory

1. Introduction to Electrodynamics, D. J. Griffiths, Cambridge University Press, 5^th Edn
2. Elements of Electromagnetics, M.N.O. Sadiku, Oxford University Press.
3. Electromagnetic Theory and Electrodynamics, Satya Prakash, Kedarnath Ramnath
4. Introduction to Electromagnetic Theory, T.L. Chow, Jones & Bartlett Learning
5. Electricity and Magnetism, B Ghosh, Books & Allied Pvt Ltd, 5^th Edn
6. Optics, Ajoy Ghatak, McGraw Hill, 8^th Edn.
7. Optics, E. Hecht and A R Ganeshan, Pearson, 6^th Edn.
8. Modern Optics, A B Gupta, Books & Allied Pvt Ltd, 6^th Edn

Practical

1. Advanced Practical Physics for students, B.L. Flint and H.T. Worsnop, 1971, Asia Publishing House.
2. An Advanced Course in Practical Physics, Chattopadhya & Rakshit, NCBA
3. B Sc Practical Physics, C L Arora, S Chand & Co
4. Advanced Practical Physics, B. Ghosh and K. G. Mazumdar, Shreedhar Publications