Sajeev John



Canada Research Chair in Optical Sciences

Tier 1 - 2001-01-01
Renewed: 2015-04-01
University of Toronto
Natural Sciences and Engineering

416-978-3459
john@physics.utoronto.ca

Research involves


The development of new materials that can carry optical signals in the same way semiconductors carry electronic signals

Research relevance


These insights will be essential to building optically based computer networks, which will be much faster and more efficient than existing computer networks

Looking to Light for the Future of Information Technology


The invention of the laser beam has changed our approach to light. We now have the ability to guide and manipulate its qualities in ways that have never been thought possible or even imaginable. Physicists like Sajeev John even refer to our new-found ability to "mold the flow of light."

Beginning in the early 1980s, John established a new mathematical theory for describing how light makes its way through different materials. Since then, his respected theory has assumed "classical" proportions. This significant contribution to the field has included techniques for scattering light through materials with different textures and densities. Now, the research is making way for a new type of medical imaging tool that uses light for the early detection of tumours.

As the holder of a Canada Research Chair, John will investigate materials that further extend the concept of molding light. Called photonic band gap (PBG) materials, they are characterized by their ability to conduct light in much the same way that semiconducting materials-such as silicon-now conduct electricity.

In fact, PBG materials could replace the current class of semiconductors in applications such as computer hardware. And their performance, limited only by the ultimate speed of light, would be much better. Above all, PBG components would continue to improve the capability of information technology. They would make it possible to exceed the restrictions that subatomic physics will soon impose on today's densely packed semiconducting components.

But before this kind of progress becomes a reality, the physical qualities of PBG materials need to be studied and understood. Engineers will need to be able to design these materials to meet the exacting specifications of high technology. They will also need to understand how PBG materials conduct light, and under what conditions they do so. In their research work, John and his colleagues will carefully consider these elements and more. And along the way, they'll be laying the foundation for an entirely new generation of high-tech hardware.