NONLINEAR OPTICS IN SILICON WAVEGUIDE ARRAYS

Applications are invited for a PhD studentship in the Department of Physics and the Centre for Photonics and Photonic Materials at the University of Bath, beginning October 2010, working under the supervision of Professor Jonathan Knight.

Silicon is the workhorse material of high technology, forming the basis of most of our modern electronics. We are extending the use of silicon into the domain of photonics, to enable a new generation of functional devices which will not be limited by being electronic. Several photons can be made to share the same space, unlike fermionic electrons which can only co-exist if they have different properties. Thus, photons ultimately offer greater opportunities for building miniature circuits than electrons. There is a flip side, however: to make devices often requires that the photons interact with one another, which they do much less easily than is the case for electrons. This nonlinear optical interaction can only take place when it is mediated by the material in which the photons are travelling: in this case, by the silicon. The work will take place in the highly supportive and collaborative group managed by Professor Knight in the broader environment of the Centre for Photonics and Photonic Materials (http://www.bath.ac.uk/physics/groups/cppm/). The research will involve working as a part of a team involving physicists from Department of Physics at Bath and engineers from the University of Glasgow who make the waveguide samples.
The project will involve doing measurements on samples specially fabricated by our collaborators in Glasgow according to our joint specification. Typically, the structures to be investigated will consist of a number of photonic nanowires on a chip, which are fabricated so that they interact with one another optically. The size scales are in the range of 200-600nm wide, with lengths of a few millimetres (see figure). The plans of exactly what samples need to be fabricated, and what tests and measurements need to be done, will be agreed at our weekly internal project meetings and our monthly video-conference meetings with our collaborators in Glasgow. Results will be discussed in an open forum with theoreticians and modellers and with the sample fabricators. Our intention is to generate high-impact scientific publications in top-grade international journals, and to give presentations on the work at conferences in Europe, the Americas and Australasia.