Department of Physics, Unit Catalogue 2006/07
PH40070 Lasers & modern optics
| Credits: 6 |
| Semester: 2|
|Before taking this unit you must (take PH20013 or take PH20060) and (take PH20017 or take PH20063) and take PH30023|
Aims: The aim of this unit is to provide a treatment of the interactions of light with matter, with particular emphasis on the generation and manipulation of laser radiation in modern optical systems.
After taking this unit the student should be able to:
* analyse the diffraction of beams, in particular the propagation of Gaussian beams;
* design simple resonant cavities and analyse their main features;
* apply matrix methods to paraxial rays in multi-element systems of lenses and mirrors;
* describe and analyse the interactions between light and matter that lead to spontaneous emission and lasing in 3- and 4-level systems;
* treat cw, mode-locked and Q-switched laser operation and describe the resulting temporal, spectral and power characteristics;
* use the index ellipsoid to analyse the changing polarisation state of light in birefringent materials and to design simple half- and quarter-wave plates;
* describe the basic features of guided modes in planar and fibre waveguides and outline basic fabrication techniques;
* describe the origins of second and third order optical nonlinearities and analyse their effects on laser light in simple cases;
* treat the effects of group velocity dispersion and self-phase modulation on short pulses, and outline briefly how solitons form in optical fibres;
* discuss and analyse the operation of simple electooptic modulators.
Numeracy T/F A, Problem Solving T/F A.
Diffractive Optics: Bandwidth of a finite pulse, diffraction at apertures, birefringence, matrix methods, Gaussian beams, laser cavities and resonators.
Lasers: Principles of laser operation, temporal and spectral characteristics, types of lasers, line-widths and broadening, Q switching and mode locking.
Manipulation of light: Dielectric waveguides, optical fibres, dispersion of short pulses, second and third order nonlinear optics, electro-optic modulation, solitons.