Metamaterials solve integral equations

As computers approach the physical limits of electronics, scientists are developing different technologies to further improve speed and capacity. Although signal processing is generally still done electronically, in 2014 Nader Engheta at the University of Pennsylvania and his collaborators proposed using metamaterials to process signals encoded in light. The device would have a spatially varying dielectric constant and would inhomogeneously scatter an incoming signal in such a way as to transform it into, say, the signal’s spatial derivative. Inspired by the idea, Engheta’s group has now used metastructures as part of a basic analog optical computer, a schematic of which is shown in the figure, that can solve integral equations.