Computing at the speed of light, that is what optical computing is all about. The field is now experiencing a real revival thanks to the huge leap in the technical ability to design and manufacture materials at the nanoscale. ‘Optical computing is so much faster.’

Metamaterials can perform analogue mathematical operations on optical signals, such as images composed of light waves. These materials are several orders of magnitude smaller than conventional optical signal processing using lenses, US professors Andrea Alú and Nader Engheta argued in Science in 2014. ‘Well-designed blocks of metamaterials can perform mathematical operations on the profile of incoming light waves as they pass through the block.’