Telecommunications is transforming
rapidly from a voice-driven to a data-driven network due to the immense success
of e-commerce and the internet in general. The corresponding rise in data
traffic can only be accomodated with a replacement of conventional ("copper")
cables by fibre optics cables, and by taking fibre optics closer to the end
user. Fibre optics used to be exclusively employed for long distance
communications, but has now begun to penetrate into the local area network.
Soon, every office will have access to an optical fibre, and the network
will reach our homes before long. In order to manage this vast amount of
data traffic, we need complex and highly integrated optical circuits, i.e.
transmitters, routers and multiplexers that are able to control many
channels simultaneously. Using current technology, such circuits quickly
become cumbersome and are difficult to mass-manufacture.
To address this problem, PICCO proposes a new generation of photonic
microcircuits that will recast integrated optics and take photonics
from the single component level to the realm of large scale integrated circuits.
The novel circuits we propose are based on submicron, high contrast waveguides,
which will be scaled-down versions of "classical" waveguides or use photonic
bandgap structures for propagation control. These waveguides offer significant
gains such as suppression of radiation losses, very tight confinement of light
and very strong diffraction and modification of the dispersion relationship,
all of which will be exploited to create ultracompact photonic circuit elements,
wavelength selective devices and efficient nonlinear elements. A particular
nonlinear device is a monolithic wavelength converter, a device that constitues
one of the key components of a versatile optical network. This device also
includes, for the first time, the combination of localised bandgap shifting
with photonic microstructures, thus paving the way for compact and fully
integrated optoelectronic circuits.
PICCO aims to demonstrate the fundamental principles of these microcircuits
and achieve similar performance as existing devices, but on a much smaller
lengthscale. Finally, PICCO will refine both the computational and the
technological tools that are required to design, fabricate and cost-effectively
mass-produce these microcircuits.
- Study the generic building blocks for advanced photonic modules, the propagation of light in sub-micron waveguides, planar photonic crystals, sharp bends and simple devices such as power splitters.
- Develop interfaces to the outside world, i.e. structures that can couple light from these microcircuits to conventional waveguides and fibres.
- Exploit the periodic nature of photonic crystal based waveguides for wavelength dependent elements in future WDM systems.
- Develop a monolithic wavelength converter that is based on difference frequency generation, periodic phase matching and strong confinement for high power density.
- Assess the promise for fabricating advanced photonic modules via deep UV lithography, thus aiming at the manufacture of low-cost micro-optic components.
- Refine existing CAD tools and develop more efficient computational code that will facilitate a much more efficient evaluation of different designs.