Photonics on silicon has been suggested since the 1970s, and previous light-beam switching devices on silicon have been demonstrated, but they were excessively large (by microchip standards) or have required that the beam of light that does the switching be very high-powered. The approach developed by Michal Lipson, Cornell assistant professor of electrical and computer engineering, confines the beam to be switched in a circular resonator, greatly reducing the space required and allowing a very small change in refractive index to shift the material from transparent to opaque.

(October 28, 2004) Blacksburg, Va.&#8212To the average American, the importance of designing semiconductors rests in the hands of the electrical engineer. But when one considers that semiconductors are integral parts of everything from video games to diagnostic medical equipment to security devices, the demand for flawless design is universal.