BBC Science

New designer materials could eventually lead to “perfect lenses” for optical devices, able to focus on features smaller than the wavelength of light.

These “metamaterials” are composites that can tap into a range of magnetism scientists cannot harness using known naturally occurring materials. The new composites are constructed using nanotechnology to build tiny circuits on a plate made of quartz.

The newest metamaterials respond in the terahertz frequency range which lies between infrared rays and microwave rays and can be made from elements, such as copper, or compounds which are not in themselves magnetic.

Electromagnetic radiation has an electrical and a magnetic component. But conventional optical lenses used in cameras, telescopes and microscopes respond to just one of the two possible fields – the electrical. This is because almost all materials are magnetically inert at optical frequencies.

Harnessing the electrical and magnetic components at optical frequencies could therefore lead to perfect lenses with vastly better resolutions than conventional optical types.

These lenses could focus on features smaller than the wavelength of light and would be limited only by the materials they are constructed from.