When Light Becomes the Processor

In a basement lab at Duke University in 2019, Patrick Bowen held a chip the size of a fingernail up to a microscope. Etched into its surface were structures smaller than a wavelength of light, optical modulators shrunk by a factor of 10,000 compared to anything the photonics industry had produced before. The modulators worked. They switched photons at speeds no electron-based transistor could match. Bowen's PhD advisor, David R. Smith, the physicist who had pioneered metamaterials research and helped build the world's first "invisibility cloak" in 2006, told him the science was settled. The engineering was not.