In modern telecommunications
the development of all-optical
equivalents for electronic signal processing devices has been the
topic of much on-going research and development effort. This research
area is focused on the development of optical signal switching
using liquid crystals.
This figure shows two nematicons interacting.
They are out of phase and form a dipole
Two-dimensional, spatial, optical solitary waves, termed nematicons, can form in liquid crystals due to a balance of the non-local response of the nematic with the diffractive spreading of the light. Liquid crystals have the potential for the development of compact photonic devices and could be the basis of optical switches in devices which do not need to operate at the large GHz telecommunication repetition rates. An advantage of photonic devices based on liquid crystals is that a nematicon can form a waveguide through which another nematicon can propagate, thus forming a light ``circuit'' which is easily re-configurable. It is anticipated that these re-configurable light circuits could form the basis for a wide variety of photonic devices.
The two figures show two nematicons interacting. In one case they are out of phase and form a dipole, while in the other they are in phase and merge.
I am working in this area with my colleagues Dr. Noel Smyth , University of Edinburgh, and Dr. Annette Worthy. This theoretical work is motivated by the award winning experimental work on nematic liquid crystals of Prof. Gaetano Assanto , University of Rome III.
Some of the projects I am working on include the development of analytical techniques to describe the evolution and interaction of nematicons, and efficient numerical techniques to solve the nematicon equations