"In modern optical communication systems, signal degradation in the optical channel caused by dispersion, nonlinearity and noise in the fibre is a critical issue. This issue is currently addressed with electronic devices using optical-electronic-optical (oeo) conversion, which are inefficient and expensive. Low power all-optical data processing devices, such as all-optical regenerators, offer an alternative solution. Optical regeneration can be promisingly performed using the four-wave mixing effect and is intended to reshape, re-amplify and retime the signal in the optical domain, which removes the need for oeo conversion and is transparent to the data rate. OSIRIS proposes to develop a multichannel regenerator based on four-wave mixing. The regenerator will be based on a photonic crystal waveguide that exploits slow light effects. Ideally, the FWM effect can be enhanced by the fourth power of the slowdown factor. This significant effect allows us to reduce the length of the device or the pump power, or both. OSIRIS will explore the extent to which this exciting promise can be realised in practise. The work will be based on specifically engineered slow light waveguides that the applicant developed during a 6-month visit to St. Andrews in 2007. Achievement of this goal will be demonstrated by realising efficient optical regeneration in an engineered slow light photonic crystal waveguide of only 100's of micrometres in length, using only mW's of optical power. This corresponds to two orders of magnitude improvement or better in device performance compared to the State-of-the-Art."