Welcome to Electromagnetic Waves & Optics (PHY-5222) Home Page

The Module Organiser is Dr. Kevin Donovan

The Deputy Module Organiser is Dr. Theo Kreouzis

Introduction

Electromagnetic Waves & Optics is a course designed for students, who have recently completed a basic course in electromagnetism. It will aim to explore the implications of this original example of physics unification in as far as it contains a full description of the behaviour of light. This course will begin by describing the properties of light in terms of the electromagnetic waves of which they are constituted answering the important question of how the intensity of a light source is related to the electric and magnetic fields describing the wave. Once we are used to using the electromagnetic wave description to obtain the intensity of light and how it interacts with the material world, reflection and refraction being the key to this aspect of light, we will be able to move on to a description of the superposition principle and the ramifications of this in terms of polarisation, interference and diffraction. Once these key areas of  physical optics are well established we will discuss optics in terms of optical instruments from the lens through a variety of instruments using geometric optics. Finally simple quantum optics will be introduced to have a model for the interaction of light with matter that describes; absorption, fluorescence and lasing.

Lectures.

There are three lectures per week taking place at the following times and venues;

Lecture 1. 10am Monday, Geog 1.26

Lecture 2. 12pm Monday, FB 2.40

Lecture 3. 12pm Wednesday, FB 2.40

Exercise Classes.

Electromagnetic Waves & Optics includes exercise classes on Thursdays and Fridays where the week's lectures will be reviewed and an opportunity offered for questions to be asked concerning that week's material. The solutions to that week's returned coursework may be covered where necessary. Set problems related to the week's material will then be worked through with the aid of the lecturer. Of the four exercise classes run each week attendance at one will be expected and the groups will be organised in week one of semester B.

There are four timetabled slots for exercise classes per week and students are expected to attend the one allocated to them. These are;

Exercise classes:

Thursday 9am - 10am & 10am - 11am,  FB 1.02.06 and 12pm - 1pm, BR 4.01

Friday 2pm - 3pm Geog 2.20

Attendance Requirements.

The department has a strong attendance policy the details of which can be found here. Attendance and performance in all aspects of this module are monitored and a student monitoring programme will maintain a record of individual student attendance at lectures and exercise classes and of homework completion.

Mid-Term Exam.

There will be a 50 minute duration mid-term exam on Monday 24th February at 10am, Geog 1.26

The exam will start at 10:05am so students are asked to make sure they arrive promptly at 10am.

Students should bring pen and other drawing tools along with a simple calculator. The answers will be written in the question book.

The exam will consist of;

Section A with brief questions requiring 1 line answers. This counts 50% to the overall mark.

Section B requiring the student to answer 2 from 3 questions. This counts 50% to the overall mark.

The Mid-Term exam is compulsory and will count 10% to the overall module assessment.

Plagiarism.

Put bluntly, plagiarism is theft by copying the work of someone else in order to gain marks or credit unfairly. It can occur in the EWO coursework as well as in written exams. It will be dealt with most severely in EWO. The Departmental policy on plagiarism and the punishments associated are explained in Policy on Plagiarism . The Course Organiser and the marker will be especially vigilant in looking out for plagiarism in coursework. If you have copied from someone else or if you have allowed your work to be copied you will be subject to the Departmental and College Disciplinary Rules. Any offence of plagiarism must be reported to the College and will be placed on your record.

Note, however, that it is a valuable part of learning to discuss exercise questions with your fellow students, but on no account should you copy solutions, or allow your work to be copied. Write your solutions and essay in your own words. Do not feel that you must hand in the complete set of exercises each week. If you have managed only half of the work, better to hand that in for marking rather than to hand nothing in or to try to copy from someone else.

Office Hours.

While generally available for questions concerning the module Dr Donovan's office hours are Wednesday 2:30 - 3:30 in physics 117.

Textbooks and Lecture Notes.

The lecture notes available on the website are both extensive and comprehensive and it is perfectly possible to study this module using those alone. For students who would like an alternative source, the textbook , Optics by Eugene Hecht, (4th Edition) is to be recommended for this module. Whilst covering all of the material that this course intends to cover, this textbook goes a lot further than is possible in a single course unit..

In the Short Loan Collection of the College Library I have ensured that there are copies of Hecht's book. There are of course many other textbooks available on a topic as broad and essential as optics.

Aims.

Maxwell’s equations and the unification of electricity and magnetism are one of the outstanding successes of the flowering of late nineteenth century classical physics and provided a model to take the unification process further just as quantum mechanics changed the popular paradigms. This course is aimed at providing the link between this successful theory and the older subject of optics through a coverage of electromagnetic wave theory and of geometric and physical optics. To bring the subject up to date an introduction into how interaction of light with matter may be simply modelled is also presented. The course will aim to make the connection between the Maxwell equations and optics via the electromagnetic wave equation, Poynting vector and the behaviour of light at dielectric interfaces including reflection and transmission coefficients. The concept of polarisation will be explored including linear and circular polarised light and birefringence. Physical optics will cover interference, diffraction and gratings. Geometric Optics will provide a basic understanding of lenses and mirrors. Instruments including the telescope, microscope and spectrometer will be discussed. Finally simple Quantum Optics will be introduced through the consideration of a quantised two level system and the Einstein coefficients used to describe the processes of absorption and optical gain from a quantum mechanical viewpoint.

Learning Outcomes

Having studied this course the student will be familiar with and have an understanding of;

1. Maxwells equations the electromagnetic wave equation the Poynting vector and  the relation between electric/magnetic fields and light intensity.

2. The  use of the EM wave equation in understanding reflection and transmission at a dielectric interface and the Fresnel equations.

3.  Simple waveguides and their modal analysis.

4. Polarisation, plane and circularly polarised light, dichroism and birefringence.

5. Interference effects; Youngs Slits, Thin film interference, Fabry-Peroy Interferometer

6. Diffraction, Fresnel diffraction and Fraunhoffer diffraction, the action and uses of diffraction gratings.

7. Lenses, compound lenses and the lens makers equation.

8. The use of lenses in optical instruments eg. the magnifying glass, Galilean telescope, Keplerian telescope and the the microscope.

9. The simple model two level quantum system and how it may be used to describe interaction of light and matter in particular; absorption, fluorescence (spontaneous emission) and lasing (stimulated emission).

Electromagnetic Waves & Optics Syllabus

Part I: Electromagnetic Waves & Physical Optics.

1. Maxwell's Equations & the Electromagnetic Wave Equation.

a) Maxwell’s equations in free space.

(i) Brief review, E, H.

(ii) The EM wave equation in free space & velocity of light.

(iii) Plane Waves, notations, ν, ω, λ, k. Spherical Waves.

b) Maxwell’s equations in simple media.

(iv) Material properties ε , μ , η, χ_E and χ_M. Magnetic Induction,  B, Displacement Field, D and Polarisation per unit volume, P .

(v) Impedance, η and the relation between E and B and  H. The Poynting vector and the relationship between electric field  and intensity.

2. Dielectric Interface & Fresnel's  Equations.

 (i) Boundary conditions, Snell's Law, critical angle, total internal reflection and evanescent fields.

(ii) Fresnel Equations. r, & R,  t & T at normal and oblique incidence. TE and TM polarisation and the Brewster angle.

3. Waveguides.

(i) Metal Waveguides.

(ii) Symmetric Dielectric Slab Waveguides. The guidance conditions, normalised frequency and the  characteristic equation.

(iii) Optical Fibres.

(iv) Dispersion and Attenuation.

4. Polarisation.

(i) Plane, circular and elliptically  polarised light.

(ii) Birefringence, half wave plates.

(iii) Kerr effect. and dichroism. Optical activity.

5. Superposition.

(i) Interference; by division of wavefront (Young's Slits) and division of amplitude (thin film interference).

(ii) The Fabry Perot interferometer, Finesse, Free Spectral Range and Resolving Power.

(iii) Temporal and Spatial Coherence.

6. Diffraction.

(i) Fraunhoffer diffraction. Single slit, double slit and multiple slit diffraction and the grating.

(ii) Fresnel diffraction.

(iii) Diffraction by apertures, rectangular and circular. The Airy disc.

Part II: Geometrical Optics.

1. Reflection & Refraction.

(i) Mirrors.

(ii) Lenses, object, image and focal planes. Lens makers equation. Simple and compound lenses.

2. Instruments.

(i) Magnifying Glass, Galilean Telescope, Keplerian Telescope and Microscope. Angular resolution.

Part III: Quantum Optics.

Einstein Coefficients and the two level system.

(i) Dexcription of absorption and Beer's law and of fluorescence using the two level system.

(ii) Population inversion and gain in a two level system.

(iii) Optical feedback in a medium with gain; The laser oscillator.

Coursework

Weekly coursework will be available on this website after the Wednesday lecture. It is to be handed in the following Wednesday before 4pm in the box provided on the first floor next to the Physics administrative offices. This time will be strictly adhered to and no late working will be accepted unless accompanied by an extenuating circumstances form. The solutions will appear later in the week on this website.The marked coursework will be placed in the pigeonhole one week later.

The courseworks along with their solutions represent a valuable revision tool.

Weekly Coursework pdf's

Coursework 1 will be found here from Wednesday of week 1. The solutions will be here after Wednesday of week 2.

Your complete weekly coursework mark record along with aggregate mark can be found here.

Please check this record regularly against the mark on your returned scripts.

Useful Information

Some useful trigonometric identities can be found here.

This is an indicative lecture schedule and is subject to alteration.

Deadlines

1. There will be one coursework per week that will be available for download on this website after  the Wednesday lecture. 

2. Hand-in of the worked problems must take place by 4:00 p.m. on the following Wednesday at the box provided outside the Teaching Administrators office on the first floor. This time will be strictly adhered to and no late working will be accepted unless accompanied by an extenuating circumstances form. The solutions will appear later in the week on this website.

3. The return of the marked problems will be by the Wednesday of the week after hand in and the scripts will be returned via the homework return boxes outside the Teaching Administrators office. 

Marking

The final assessment of this module will be comprised of three components as follows;

1. There will be Weekly Coursework set and the total mark from the coursework will comprise 10% of the overall module assessment.

2. There will be a 50 minute MidTerm exam in the first lecture slot following reading week and the mark from the midterm will comprise 10% of the overall module assessment.

3. There will be a Final Exam in May/June and the mark from the final exam will comprise 80% of the overall module assessment.

Past Exams & Solutions

The 2010 EWO exam can be found here.

The 2011 EWO exam can be found here.

The 2012 EWO exam can be found here.

The 2013 EWO exam can be found here.

The 2012 EWO exam solutions can be found here.

The 2013 EWO exam solutions can be found here.

Exercise Class

Electromagnetic Waves & Optics includes exercise classes on Thursdays & Fridays where the week's lectures will be reviewed and an opportunity offered for questions to be asked concerning that week's material. The solutions to that week's returned coursework may be covered where necessary. Set problems taken from past exams and related to the week's material will then be worked through. The solutions to these problems will be posted here on the following Sunday/Monday. Of the four exercise classes run each week attendance at one will be expected.

The exercise class groups can be found here. 

Exercise class 1 week will be found here.

Lecture notes

Lecture notes 1 including; Maxwell’s Equations, Wave Equation, Relationship between E & B, Relationship between I & E. Simple media, susceptibility permittivity and & refractive index are available here. (20 pages, 86kB).

Lecture notes 2 including; Dielectric interface, boundary conditions, reflection&refraction (Snells Law), TIR, evanescent fields. Reflection and transmission, normal and oblique incidence, Fresnels equations will be available here. (39 pages, 212kB).

Lecture notes 3 including; Metal waveguides and modes, symmetric slab waveguide & guidance conditions, U,W,V & characteristic equation will be available here. (30 pages, 185kB).

Lecture notes 4 including;Plane polarised light, circularly polarised light & elliptically polarised light. Birefringence, wave plates and polarisation shifters. Linear and circular dichroism will be available here. (31 pages, 136kB).

Lecture notes 5 including; Interference and the interference term. Interference by division of wavefront and Young’s slits. Interference by amplitude division; thin film interference, multiple reflections, transmission and reflection and coefficient of Finesse. The Fabry Perot resonator/etalon. Free spectral range, resolving power and resolution will be available here (38 pages, 249kB).

Lecture notes 6 including; Diffraction, Fraunhoffer & Fresnel. The single slit, double slit, multiple slit & diffraction grating. Rectangular aperture, circular aperture, diffraction limited optics will be available here (65 pages, 366kB).

Lecture notes 7 including; Geometric Optics, Refraction at curved surface, the lens makers equation, Gaussian Lens formula, Newton’s formulation. Compound lenses. Corrective optics, magnifying glass, microscope and telescopes will be available here. (54 pages, 186kB).

Lecture notes 8 including; Absorption fluorescence and stimulated emission in a two level system, Einstein coefficients, optical gain, feedback and laser oscillation will be available here. (21 pages, 195 kB)

Revision Aids.

Exam Revision Aids.

A comprehensive set of the complete coursenotes condensing the 300 plus pages of the full notes into 56 pages is will be available here at the end of the course.

The complete set of coursework plus solutions and past exams plus solutions will also be of help in revision as will the exercise class problems.

Mid Term Revision.

A condensed version of the lecture notes (34 pages) for the first six weeks of the module will be available here just before reading week. These are a useful revision aid for the Mid-Term Exam.

News:

No news is good news as your mother always tells you. Enjoy all this good news!