Photonics and Optoelectronic Devices – (M.Sc.)

Contents

Organisation

Teaching comprises lecture modules, tutorials, and laboratory work. Students move their accommodation from St Andrews to Heriot-Watt university part way through the teaching session (near the start of February).

Students are also expected to attend relevant research seminars and departmental colloquia which are held regularly, and which reflect the research interests of the physics departments in St Andrews and Heriot-Watt. Seminars and Colloquia are given by departmental research staff, specialists from other universities and specialists from industry.

Assessment

Work for lecture modules is assessed through examinations whereas the laboratory work is assessed in a continuous manner. Lecture courses are examined at the end of each teaching block.

The project placement which occupies 12 weeks within June, July and August is assessed in September after the submission of a dissertation and an oral exam.

Course and Syllabus

1. Lasers

Introductory Laser Physics (St Andrews, 27)

This module presents a basic description of the main physical concepts upon which an understanding of laser materials, operations and applications can be based. The syllabus includes: basic concepts of energy-level manifolds in gain media, particularly in respect of population inversion and saturation effects; conditions for oscillator stability in laser resonator configurations and transverse and longitudinal cavity mode descriptions; single longitudinal mode operation for spectral purity and phase locking of longitudinal modes for the generation of periodic sequences of intense ultrashort pulses (i.e. laser modelocking); illustrations of line-narrowed and modelocked lasers and the origin and exploitability of intensity-induced optical effects.

Advanced Laser Physics (St Andrews, 27)

Quantitative treatment of laser physics embracing both classical and semiclassical approaches; transient/dynamic behaviour of laser oscillators including relaxation oscillations, amplitude and phase modulation, frequency switching, Q-switching, cavity dumping and mode locking; design analysis of optically-pumped solid state lasers; laser amplifiers including continuous-wave, pulsed and regenerative amplification; dispersion and gain in a laser oscillator-role of the macroscopic polarisation; unstable optical resonators, geometric and diffraction treatments; quantum mechanical description of the gain medium; coherent processes including Rabi oscillations; semiclassical treatment of the laser; tunable lasers.

Ultrafast Photonics (Heriot-Watt, 10)

Pico/femtosecond techniques. Standing wave and travelling wave resonators. Active and passive modelocking schemes. Saturable gain and loss. Nonlinear optical effects for enhanced modelocking. Application examples and measurement techniques associated with ultrashort laser pulses.

2. Modern Optics

Nonlinear Optics and Modulators (St Andrews, 20)

Phenomenological theory of nonlinearities. Optics of anisotropic media. Harmonic generation, mixing and parametric effects. Two-photon absorption, saturated absorption and nonlinear refraction. Rayleigh, Brillouin and Raman scattering. Self-focusing and self-phase-modulation. Self-induced transparency. Solitons. Optical switching. Electro-optic effect and acousto-optic effects. EO and AO modulators.

Optifal Design, Fourier Optics & Holography(Heriot-Watt, 20)

Revision of geometrical optics. Fourier transforms. Impulse response and transfer functions. Scalar diffraction, spatial and temporal coherence. Image forming systems, coherent and incoherent imaging. Spatial filtering. Holography (Fresnel, Fraunhofer, Fourier). Holographic techniques and applications.

Photonics in BioMedicine (St Andrews, 20)

The course will expose students to the exciting opportunities offered by applying photonics methods and technology to biomedical sensing and detection. A rudimentary biological background will be provided where needed. Topics include fluorescence microscopy and assays including time-resolved applications, optical tweezers for cell sorting and DNA manipulation, photodynamic therapy, lab-on-a-chip concepts and bio-MEMS. This course will be taught as lectures, including guest lectures by specialists, and problem-solving exercises.

3. Photonic Materials

Semiconductor Physics (10)

Band gaps, density of states, materials, optical and electronic properties, carrier generation and recombination, mobility and diffusion, low dimensional structures, quantum wells, wires and dots, heterostructures.

Polymers and Liquid-Crystals (10)

Semiconducting polymers - photoluminescence and electroluminescence. Factors determining efficiency; light-emitting diodes and field effect transistors. Liquid crystals - nematic, smectic and cholosteric phases; director and order-parameter; operation of twisted nematic display.

Materials Growth & Fabrication (10)

Growth of optoelectronic materials by MBE, MOCVD, Plasma CVD, photochemical deposition. Epitaxy, interfaces and junctions (advantages/disadvantages of growth methods, of interface quality, interdiffusion and doping. Quantum wells and bandgap engineering (examples of structures). Post-growth processing (patterning by photolithography, contacting, annealing)

4. Optoelectronic Devices

Semiconductor Devices (20)

PN junctions, solar cells, LEDs, gain conditions, rate equations, spectra, lasers, waveguides and VCSELs. Semiconductor optical amplifiers, optical modulators, all-optical switches. Detectors.

Telecommunications & Optical Fibres (20)

Attenuation and dispersion. Chirp, dispersion management. Numerical aperture. Optical time domain reflectometry. Optical transmitters. Optical receivers. Fibre amplifiers: EDFA, PDFA & Raman. Digital systems. Analogue systems. Coherent systems. Public communication network. WDM and Filters: dielectric, AWG and fibre grating devices Nonlinear fibres: SPM, CPM, MI, FWM, SBS, SRS Fibre optic sensors.

Optical Instrumentation and Sensors (10)

Optical metrology; interferometry, fundamental length metrology, transfer of the length standard. Optical fibres sensors; gyroscopes, hydrophones, strain and temperature sensing, grating & distributed sensors. Engineering optical diagnostics; vibrometry and velocimetry, speckle interferometry.

Photonic Crystals(8)

Photonic crystals, wave propagation, applications to high-efficiency emitters, miniaturised photonic circuits and dispersion engineering.

5. Technical Communication and Business Awareness

Optoelectronics in Industry

A series of around 15, two-hour sessions given by lecturers from Industry. Examples from the current programme are: Laser safety. Optical techniques in the automotive industry. Aerospace applications of photonics. Engineering management. Pulsed laser material processing. Future optoelectronics research.

Innovation & Team Work ~ 20 hours.

The course will involve lectures, "practical" sessions, and team-work in which a product is taken from inception to sales and servicing. Lecture topics are: Invention in a commercial setting, driving forces, challenging linear thought, the inventive step, engineering & rethinking, IPR & patents, following through with the product.

Business Awareness

Aspects not covered by the above sessions (patents, IPR, business formation, venture capital, the planning process, negotiation, the leadership process)

Literature surveys & Report writing

All full-time students carry out one minor literature survey, from a selection of topics. In addition they carry out a major survey and write a report on the topic area of the summer research project. This has the added benefit of establishing the projects in good time, and means that the student is well prepared in the topic when he/she starts the project in early June.

Poster & Oral presentations

At the time of the Industrial Advisory Committee meeting (spring), all students prepare and present posters covering one of their laboratory experiments. Both the scientific content and the presentation are judged. Students are also assited to give talks on a topic of interest.

6. Laboratory and Project Work

The well-equipped photonics teaching laboratories at the two sites give students a range of useful practical experience. Students spend three afternoons a week in these labs.