InP / AlGaInP Quantum Dot Lasers for 650-780nm Emission

This project is about the development of a new material with nanoscale features that has properties that go beyond those of existing materials and will enable a number of applications that require light sources with properties that are not currently available. The applications include photodynamic therapy, which is a cancer treatment in which singlet (reactive) oxygen is generated at a specific location by using high power light with a photon energy sufficient to disassociate the oxygen molecule; DVD based optical storage, that requires dual wavelength sources to ensure backwards compatibility in new systems and which is necessary to support the semiconductor wafer manufacturing base within the UK; optical sensing, one form of which requires dual wavelength sources; and fluorescence lifetime studies, that are used, for example, for monitoring biological processes. We aim to demonstrate working devices that utilise this quantum dot material for these specific applications but also to investigate and demonstrate the basic material properties and the basic material and device physics to allow an even broader range of applications in the future. We will employ new strategies to grow material with the particular properties we require, we will characterise this material with a range of advanced experimental techniques, some of which we will develop particularly for this purpose, and will report on the properties of the material and the operation of working devices with new functionality.