Canadian Physicists predict cooler computers

Canadian physicists say they have discovered new behaviours of light occurring within photonic crystals.

University of Toronto quantum optics researchers Professor Sajeev John and doctoral student Xun Ma said their findings could lead to faster optical information processing and compact computers that don't overheat.

"We discovered that by sculpting a unique artificial vacuum inside a photonic crystal, we can completely control the electronic state of artificial atoms within the vacuum," Ma, lead author of the study, said. "This discovery can enable photonic computers that are more than 100 times faster than their electronic counterparts, without heat dissipation issues and other bottlenecks currently faced by electronic computing."

John said he and Ma designed a vacuum in which light passes through circuit paths whose character changes drastically and abruptly with the wave length of the light.

"A vacuum experienced by light is not completely empty, and can be made even emptier," said John. "It's not the traditional understanding of a vacuum."

Ma added: "In this vacuum, the state of each atom -- or quantum dot -- can be manipulated with color-coded streams of laser pulses that sequentially excite and de-excite it in trillionths of a second. These quantum dots can in turn control other streams of optical pulses, enabling optical information processing and computing."

The research is reported in the journal Physical Review Letters.