Tiny Lasers Could Make Microprocessors Faster, Less Power-Hungry: Study

By fabricating tiny lasers directly on silicon, an international group of scientists has found a way that could make microprocessors run faster without consuming more power.

The group of scientists from Hong Kong University of Science and Technology, the University of California, Santa Barbara, Sandia National Laboratories and Harvard University grew tiny high-performance lasers directly on silicon wafers.

Reported in the journal Applied Physics Letters, the group said integrating sub-wavelength cavities - the essential building blocks of tiny lasers - onto silicon enabled them to create and demonstrate high-density on-chip light-emitting elements.

"Putting lasers on microprocessors boosts their capabilities and allows them to run at much lower powers, which is a big step toward photonics and electronics integration on the silicon platform," said professor Kei May Lau from Hong Kong University of Science and Technology.

The scientists used "tiny whispering gallery mode lasers - only 1 micron in diameter - that are 1,000 times shorter in length and 1 million times smaller in area than those currently used."

In terms of applications, the group's tiny lasers on silicon are ideally suited for high-speed data communications.

"Our lasers have very low threshold and match the sizes needed to integrate them onto a microprocessor," Lau pointed out. "And these tiny high-performance lasers can be grown directly on silicon wafers, which is what most integrated circuits (semiconductor chips) are fabricated with."