Module Overview

Electromagnetism & Stat Physics

This module comprises two parts. Part A is on Electromagnetism and Part B is on Statistical Physics

Part A of this module develops the principles of electromagnetism and their application to waveguides and optics.

Part B of the module develops the principles of statistical physics and their application to thermal physics.

Module Code

PHYS 4842

ECTS Credits


*Curricular information is subject to change

Part A - Electromagnetism

  • Review of wave view of light, Maxwell’s equations, plane waves, propagation in a medium, phase and group velocity. Mechanical oscillator model for non-conducting solids, dispersion, complex refractive index, absorption, normal and anomalous dispersion variation of refractive index with frequency, refractive index approximations.
  • Behaviour of light at an interface: Fresnel’s equations, reflectance, Brewster angle, phase shifts on reflection, thin film coatings, multilayer stacks, filters and reflectors, Total internal reflection
  • Dielectric waveguide propagation, existence of modes, waveguide mode equation, mode cut off, mode intensity distribution. Dielectric cavities and energy storage.


Part B - Statistical Physics

Topics chosen from:

  • Statistical methods in physics. Microstates and macrostates. Counting microstates.
  • The meaning of entropy. S = k ln W. The Boltzmann distribution.
  • The entropy S and the free energy F in terms of the single particle partition function (p.f.) Z. Evaluation of translational partition function, Ztrans, rotational partition function, Zrot and the vibrational partition function, Zvib.

Application to monatomic perfect gases and to rigid and non rigid perfect diatomic gases. The Sachur-

  • Tetrode equation.
  • Gibb’s paradox. Distinguishability and indistinguishability.
  • Simple two level solids. The Schottky effect.
  • Maxwell-Boltzmann distributions of speed and velocity of gas particles.
  • Fermi-Dirac and Bose-Einstein distributions.
  • The application of Fermi-Dirac statistics to electrons in a metal.
  • The application of Bose-Einstein statistics to a photon gas. Blackbody radiation curves. Ortho- and para- hydrogen.
  • Einstein and Debye models of the solid state. Phonon gas.

Temperature variation of the principal specific heat, cV.

Laboratory exercises aligned with module content. 

Lectures, tutorial sheets and class tutorials and laboratory.

Module Content & Assessment
Assessment Breakdown %
Formal Examination60
Other Assessment(s)40