Ultrafast Photonic Computing Processor Uses Polarization

Researchers from the University of Oxford have developed a method using the polarization of light to maximize information storage density and computing performance using nanowires. Similar to how different wavelengths of light do not interact with one another — allowing fiber optic cables to carry multiple parallel streams of data — different light polarizations do not interact.

Each polarization can be used as an independent information channel, enabling more information to be stored in multiple channels, greatly enhancing information density.

A photonic chip developed by the universities of Oxford and Exeter exploits polarization properties to boost performance. Courtesy of June Sang Lee/University of Oxford.

“We all know that the advantage of photonics over electronics is that light is faster and more functional over large bandwidths,” said June Sang Lee, first author of the paper. “So, our aim was to fully harness such advantages of photonics combining with tunable materials to realize faster and denser information processing.”

In collaboration with C. David Wright, a professor of electronic engineering at the University of Exeter, the team developed a hybridized-active-dielectric nanowire, using a hybrid glass material that shows switchable material properties upon the illumination of optical pulses. Each nanowire demonstrates selective responses to a specific polarization direction, so information can be simultaneously processed using multiple polarizations in different directions.

Hybrid nanowires that can selectively switch the devices depending on polarization. Courtesy of June Sang Lee/University of Oxford.

The researchers reported that in using this concept they developed what they claim is the first photonic computing processor to use polarizations of light. The nanowires are modulated by nanosecond optical pulses that enable the chip to conduct computing operations over multiple polarization channels, leading to an enhancement in computing density by several orders compared to that of conventional electronic chips.

The research was published in Science Advances (www.doi.org/10.1126/sciadv.abn9459).