Researchers have created a new type of optical device small
enough to fit millions on a computer chip that could lead to
faster, more powerful information processing and supercomputers.
The "passive optical diode" is made from two tiny silicon rings
measuring 10 microns in diameter, or about one-tenth the width
of a human hair. Unlike other optical diodes, it does not
require external assistance to transmit signals and can be
readily integrated into computer chips. The diode is capable of
"nonreciprocal transmission," meaning it transmits signals in
only one direction, making it capable of information processing,
saidMinghao Qi (pronounced Chee), an associate professor of
electrical and computer engineering at Purdue University. "This
one-way transmission is the most fundamental part of a logic
circuit, so our diodes open the door to optical information
processing," said Qi, working with a team also led byAndrew
Weiner, Purdue's Scifres Family Distinguished Professor of
Electrical and Computer Engineering. Th