Researchers Propose Lossless Nano-Optical Cables

New research proposes lossless nano-optical fibers small enough to replace copper wiring in computer chips.

“We’re already transmitting data from continent to continent using fiber optics, but the killer application is using this inside chips for interconnects — that is the Holy Grail,” said University of Alberta professor Dr. Zubin Jacob, whose team modeled the metamaterial fiber.

At present, fiber optic cables are limited to about a micron in diameter. The proposed fibers would be 10 times smaller, according to the researchers, and able to compress and contain light waves without creating heat, slowing the signal or losing data.

Integrating nanoscale electronics and conventional optics is restricted by the diffraction limit of light, the researchers said, adding that metals can confine light at the subwavelength scale but are susceptible to signal loss, while dielectrics do not confine evanescent waves, leading to cross-talk between components.

“What we’ve done is come up with a fundamentally new way of confining light to the nanoscale,” Jacob said.

The researchers propose fibers made with a silicon core and cladding integrating germanium nanowires and porous silica, which they said would control the optical momentum of evanescent waves, eliminating loss.

The researchers hope to use the new approach to develop a class of waveguides that outperforms the cross-talk performance of existing photonic structures by one order of magnitude.

The work was funded by the Natural Sciences and Engineering Research Council of Canada and the Helmholtz-Alberta Initiative.

The research was published in Optica (doi: 10.1364/optica.1.000096).

For more information, visit www.ualberta.ca.