Bending Light the 'Wrong' Way: Study Suggests Simple Way To Make Near-perfect Lenses

Researchers have devised a strikingly simple method of producingmaterials which bend light the 'wrong' way -- a significant developmentas lenses with minimal distortion can be made from flat slabs of thesenegatively-refracting materials. In technological fields where lensesare key components, such as telecommunications, microwave engineeringand optical engineering, negatively-refracting materials which can becheaply produced are expected to have a revolutionary impact.

Although scientists have sought to minimize lens distortion forcenturies, it is only within the past five years that the production ofnear-perfect lenses has become a realistic possibility. Progress hasbeen made possible with the recent creation of negatively-refractingmaterials which enable rays of light, passing from one material toanother, to bend in the opposite direction to that described inconventional physics textbooks.

However, these negatively-refracting materials are difficultand costly to produce, as they involve complex assemblies ofintricately-shaped conducting components embossed on non-conductingplatforms. A study by Dr Tom Mackay, of the University of Edinburgh,and Professor Akhlesh Lakhtakia, of Pennsylvania State University,suggests a much simpler method of construction.

The new study, reported in Microwave and Optical TechnologyLetters, shows that rather than creating complex and costlymicroelectronic devices, negatively-refracting materials can instead beproduced by simply blending two granular substances together. Neitherof the two granular substances can refract negatively by itself.However, the study predicts that a homogeneous mixture of these twosubstances can refract negatively, provided the relative properties andproportions of the substances are chosen appropriately.

Dr Tom Mackay, of the University of Edinburgh's School ofMathematics,said: "Through its simplicity, this method represents an excitingbreakthrough for inexpensive exploitation of negative refractiontechnologies. The prospects for near-perfect lenses, and beyond, bringsdreams a step closer to reality."

Reference: 'Negative phase velocity in isotropic dielectric-magneticmediums via homogenization' by T.G. Mackay and A. Lakhtakia, acceptedfor publication in Microwave and Optical Technology Letters, andavailable athttp://www.arxiv.org/abs/physics/0505005