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Centre for Doctoral Training in Photonic Integration and Advance Data Storage

Steffan Gwyn

Steffan Gwyn

Steffan joined the CDT in September 2016, having previously completed an MSci in Physics at the University of Manchester.

In the first semester of 2016/17 he completed a short exploratory practical research project at the University of Glasgow, supervised by Professor Anthony Kelly - Analysis of a optically preamplified receiver. In the second semester, under the supervison of Dr Fumin Huang, he completed a short research project at Queen's University Belfast - Engineering the optical properties of refractory plasmonic materials.

CDT PhD Project - GaN blue lasers for photonic integration

Supervisors: Professor Anthony Kelly, University of Glasgow and Professor Robert Bowman, Queen's University Belfast

Semiconductor gallium nitride laser diodes emitting in the blue play a key role in a range of applications including medical instrumentation, visible light communications and quantum technologies in addition to their use as sources for lighting when used in tandem with colour converters for white light generation. They also offer an interesting solution to generate sources of UV radiation by non-linear up conversion, which would be of great interest for compact and cheap systems for disinfection and sterilisation processes. However, the immaturity of GaN technology is still a major barrier to the full development and exploitation of some of these applications.

This project will explore a number of different GaN photonic integrated circuits, including monolithic integration of gratings with laser diodes for frequency selection and control, multi lasing elements for wavelength multiplexing in optical communications and, more generally, a platform for optical integration with passive optical components.

Given the large emerging markets and applications, this area is potentially very rich in terms of impact, future funding and commercial relevance.

Queen's University Belfast Crest

University of Glasgow Crest