April 19, 2013

Scientists spin photons to send light in one direction




Researchers at King's College London have achieved previously unseen levels of control over the travelling direction of electromagnetic waves in waveguides. Their ground-breaking results could have far-reaching benefits for the way light is controlled in optical waveguides and fibres, significantly improving integration, efficiency and speed.

In a paper published today in Science, Professor Anatoly Zayats and his team, working with collaborators from Universitat Politècnica de València in Spain, show how their use of circularly polarised light - light containing spinning photons (fundamental particles) - and metallic nanostructures achieve a ‘water wheel’ effect to send light waves in a single direction along a metal surface. Their findings are surprising because such unidirectional waves have not been controlled in this way before. The research has profound implications for optical communications and information processing technologies.