Module Information

Module Identifier
PH34510
Module Title
Lasers and Photonics
Academic Year
2024/2025
Co-ordinator
Semester
Semester 1
Pre-Requisite
Reading List

Course Delivery

 

Assessment

Assessment Type Assessment length / details Proportion
Semester Assessment 2 x Assignments  (15% each)  30%
Semester Exam 2 Hours   Written Examination  70%
Supplementary Exam 2 Hours   Written Examination  100%

Learning Outcomes

On successful completion of this module students should be able to:

Describe what is meant by laser light, in the context of the functionality of different types of laser systems, and appreciate the importance of lasers as scientific and technological tools.

Classify the major causes of attenuation and dispersion of light in optical fibres and analyse the means by which these can be minimised.

Analyse the design of optical modulators/devices, based on the electro-optic and acousto-optic effect, and the non-linear interactions of intense laser light.

Describe and evaluate the mechanisms of iridescence and structural colour in photonic crystals, in terms of dielectric periodicity in optical structures and the formation of optical band-gaps.

Derive the basic principles of optical hologram formation, and thus describe the key elements of practical holography.

Present a qualitative appreciation of the concepts of “Quantum Optics”; where photons of light are treated as quantum mechanical entities.

Brief description

This module will cover a number of topics in Modern Optics, with a particular theme of how photons can replace electrons as the principal information-processing agents. The module will discuss optical sources (including lasers in detail), optical fibres and waveguides, non-linear optical effects, optical modulation and signal processing, photonic structures, holography and optical storage.

Content

LASERS
Absorption, spontaneous emission of radiation and the Einstein relations.
Laser radiation theory leading to the necessity for population inversion.
Population inversion and three- and four-level systems.
Threshold condition for laser cavities and mode structure of laser light.
Examples of practical laser systems including solid state lasers, gas lasers, excimer lasers, dye lasers and semiconductor lasers.
Continuous wave and pulsed lasers; theory of mode-locking, ultra-fast lasers.

OPTICAL FIBRES
Snell's law, dispersion and attenuation in optical fibres.
Single mode and graded index fibres.
Materials for optical fibres, fibre manufacturing.

NON-LINEAR OPTICS
Polarisation effects in media, harmonic frequency generation.
Parametric generation of light, white-light continua.
Other nonlinear processes; e.g. Kerr effect, multi-photon absorption.

MODULATION OF LIGHT
Birefringence and electro-optic modulators.
The acousto-optic effect.

PHOTONIC CRYSTALS
The basics; periodicity in optical structures.
Optical band-gaps, group velocity dispersion and optical density of states.
Modeling of photonic crystals, plane-wave and FDTD simulations.
Practical realisations of photonic crystals, iridescence and structural colour, integrated optics.
Introduction to Plasmonics.

HOLOGRAPHY
Basic principles.
Practical examples; the Gabor hologram, volume holograms.
Holographic lithography & optical data storage.

Module Skills

Skills Type Skills details
Real world sense Demonstrating links between the physics of lasers & photonics with technological and industrial applications.

Notes

This module is at CQFW Level 6