Light has an exploitable property—different wavelengths of light do not interact with each other—a characteristic used by fiberoptics to carry parallel streams of data. Similarly, different polarizations of light do not interact with each other either. Each polarization can be used as an independent information channel, enabling more information to be stored in multiple channels, hugely enhancing information density.

First author and DPhil student June Sang Lee, Department of Materials, University of Oxford said: "We all know that the advantage of photonics over electronics is that light is faster and more functional over large bandwidths. So, our aim was to fully harness such advantages of photonics combining with tunable material to realize faster and denser information processing."

In collaboration with Professor C. David Wright, University of Exeter, the research team developed a HAD (hybridized-active-dielectric) nanowire, using a hybrid glassy material which shows switchable material properties upon the illumination of optical pulses. Each nanowire shows selective responses to a specific polarization direction, so information can be simultaneously processed using multiple polarizations in different directions.

Using this concept, researchers have developed the first photonic computing processor to utilize polarizations of light.

Photonic computing is carried out through multiple polarization channels, leading to an enhancement in computing density by several orders compared to that of conventional electronic chips. The computing speeds are faster because these nanowires are modulated by nanosecond optical pulses.