Nanoscale lasers...

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Intel and UC Berkley were the first to bond Indium Nitride lasers to Silicon, but the process was costly to manufacture within the limits of standard chip technologies.

Dr. Connie Chang-Hasnain's research group at UC Berkley has overcome the problem of the mismatch between Gallium Arsenide and Silicon crystal structures (100 and 111-Zincblende, respectively) by letting "them grow tapered hexagonal pillars of indium-gallium arsenide with bases only about half a micrometre across onto silicon chips. The semiconductors were grown using chemical vapour deposition in the same way that LEDs are created. These nanopillars act as lasers when an external laser shines on their top: the laser light bounces around inside the pillar, following a helical path from top to bottom, where some of the light leaks out.

"In practical applications, the researchers expect that the nanolasers will be able to produce their own light, without the need for an external laser.

"This demonstration is a crucial step on the path to integrating optics and electronics, but many remain to be made before we reach the goal, says lead author Roger Chen, also at the University of California, Berkeley."

New Scientist's links:

Laser-making chip promises data transfer boost

First lasers grown directly on silicon chips