The Descartes Prizes are awarded by the European Union, supported under the European Commission's Sixth Framework Programme, within the Research Directorate Science and Society. It is one of Europe's foremost scientific awards.

The Descartes Prize for Research has been awarded yearly, since 2000, to transnational research teams which have achieved outstanding scientific or technological research results through collaborative research in any field of science, including economics, social sciences and humanities. The amount of the prize, shared among the laureates, is one million euros.

Primarily an award to encourage cooperation between European nations, the Descartes Prize celebrates team efforts rather than individual researchers. The work of teams is judged on "the criteria of excellence and cross-border cooperation, and the necessary balance between the two."

More information can be found at the Descartes website.

For the Descartes Research Prize, the Grand Jury, chaired by Ene Ergma, Vice President of the Academy of Sciences of Estonia and President of the Estonian Parliament, chose five laureates from a highly competitive field of 85 entries. The teams which will receive €200,000 each are:

• the EXEL team for developing a new class of artificial meta-materials, called Left-Handed Materials or Negative Index Materials, which have the ability to overturn many familiar properties of light;
  
• the CECA team for breakthrough findings on climate and environmental change in the Arctic;
  
• the PULSE team for demonstrating the impact of European pulsar science on modern physics;
  
• the ESS project, European Social Survey, for radical innovations in cross-national surveys; and
  
• the EURO-PID project for cutting-edge research on a group of over 130 rare genetically determined diseases known as primary immunodeficiencies.

[Above: Team EXEL accepts the Descartes Prize. The awards ceremony was held at the Royal Society in London on December 2, 2005.]

Team EXEL is a multi-national research team whose members include:

• Costas Soukoulis, (Team Leader) Ames Laboratory, Iowa State University and the Institute of Electronic Structure and Laser, Foundation for Research and Technology, Heraklion, Crete, Greece.
• Eleftherios Economou, Foundation for Research and Technology, Heraklion, Crete, Greece.
• Sir John B. Pendry, Imperial College London, UK.
• David R. Smith, Duke University, US.
• Ekmel Ozbay, Bilkent University, Turkey.
• Martin Wegener, University of Karlsruhe/DFG-Centre for Functional Nanostructures, Germany.

About Team EXEL:
The discovery of novel natural or artificial materials capable of controlling the propagation of electromagnetic waves is of central importance to both science and technology (telecommunications, imaging, etc.). Three breakthroughs in this field have taken place in the last twenty years: plasmon optics, photonic crystals (PCs) and more recently negative index materials (NIMs) or left-handed materials (LHMs). Members of EXEL have been prime movers or initiators in these fields: The teams at FORTH [Soukoulis (also with Ames Laboratory and Iowa State University), Economou, Kafesaki] and Bilkent (Ozbay) played a central role in the initiation and development of PCs. The team at Imperial (Pendry, Wiltshire) and Duke (Smith, Schurig, initially at UCSD) realized for the first time a novel composite material exhibiting, over a finite band, negative permittivity, negative permeability and, consequently, negative index of refraction, thus extending the realm of electromagnetism and demonstrating novel counterintuitive effects (such as reversal of Snell's law and Doppler effect, opposite phase and group velocity). In addition, Duke/UCSD was the first to demonstrate experimentally negative refraction in such a material. This marked the beginning of the development of the scientific pursuit of NIMs and also the beginning of what has been a productive and fruitful collaboration between the US and several European nations, culminating in some of the highest frequency artificial materials being produced in collaboration with the team at Karlsruhe (Wegener, Linden).

The revolutionary concept of negative refraction initially prompted many objections, based on the perceived violations of causality, of momentum conservation and of Fermat's Principle. EXEL firmly refuted all of the objections. Furthermore, we jointly developed multiple procedures to retrieve unambiguously the effective permittivity and permeability (both real and imaginary parts) from the transmission and coefficients and other types of simulated and experimentally acquired data, providing a firm foundation for the design, implementation and analysis of these novel materials. [Left: Team Leader, Costas Soukoulis, at the awards ceremony].

Having addressed the fundamental physics issues of NIMs, team EXEL showed that a properly designed NIM planar slab could amplify and refocus the evanescent waves associated with a nearby electromagnetic source (like an antenna). This phenomenon of evanescent wave refocusing led Pendry to predict that the NIM slab could be used as a "superlens," able to achieve image resolution beyond the diffraction limit. In further exploration of the real world limitations of the superlens, team EXEL showed that significant resolution enhancement could be obtained even in with the practical limitations of practical materials. The road map developed under the EXEL collaboration paved the wave for the first experimental demonstration of superlensing at visible wavelengths, reported in the journal Science this year. [Right: Sir John Pendry and Ekmel Ozbay observe the proceedings]. EXEL has also shown that a properly designed PC can exhibit negative refraction, and has demonstrated for the first time sub-wavelength imaging resolution both in simulations as well as in experiments.

EXEL's team members have combined various fabrication methods, experimental techniques, sophisticated simulations and analytical reasoning to allow the sign of the refractive index to be correctly determined. These techniques form the basis for the analysis of higher frequency NIMs. As the team has progressed towards higher frequency structures, EXEL has produced modified designs that are easier to fabricate, are more compact, can be matched to free space and are amenable to numerous applications. In this development, EXEL has demonstrated a NIM with the lowest known attenuation (-0.3 dB/cm at 4 GHz) and has developed a variety of 2- and 3-dimensional NIM designs. [Left: Staircase in the Royal Society].

A significant challenge for NIMs has been to extend the band of NIM frequencies from the GHz range where initial experiments were performed to either low frequencies, where MRI applications can be targeted, or to higher frequencies, where telecommunications applications can be accessed. EXEL has demonstrated low frequency magnetic structures for MRI applications based on the Swiss Roll design. In addition, EXEL has also fabricated artificial magnetic materials operating at 6 THz, 100 THz and 200 THz (1.5 micron wavelength). These are the highest frequency structures demonstrated worldwide.

In summary, team EXEL has been instrumental in creating and developing a new revolutionary field, which extends the realm of electromagnetism and opens up new technological possibilities.