Light from silicon-based lasers has always been too erratic to be of any practical use. But two experiments reported last week raise hopes that the lasers will eventually be steady enough to drive ultra-fast optical microchips. Both experiments use light from an external laser to “pump” the silicon atoms into a state in which they can emit light.
Engineers at Intel in California got a silicon laser to produce a steady beam by guiding the pumping laser through an S-shaped path in a silicon wafer (Nature, vol 433, p 725). The longer path means the pumping light can be…
