Information superhighway
- an optical glass fiber as thin as a human hair- is a highway
of light where light particles, or photons, carry information. Information
processing, on the other hand is primarily done with electronics
built on flat semiconductor wafers of Silicon, Germanium
and GaAs. What
this means is that information has to be converted back and
forth from photons to electrons back to photons, and so on. The
interface between an optical fiber and a semiconductor chip
is not straight forward, and is currently done with relatively
crude engineering. That is the status today of what is
called “optoelectronics.”
Now that paradigm might change to All-fiber optoelectronics, with
a paper published recently in the journal Science (SCIENCE
VOL 311, p. 1583, 17 MARCH 2006) by Penn State and University
of Southampton researchers.
|
 |
A Germanium Broom! A
silica optical fiber passing through the eye of a needle. The
end of the fiber is etched to reveal hundreds of germanium wires
deposited inside the fiber, each a hundred times smaller than
a human hair. |
|
John Badding (chemistry), Venkatraman
Gopalan (MatSE), Vincent
Crespi (Physics), along with Pier Sazio (U.K)
have demonstrated a hybrid technology that seamlessly integrates
key aspects of both fiber optics and electronics disciplines,
by demonstrating the fabrication of tubes, solid nanowires,
coaxial heterojunctions, and longitudinally patterned structures
composed of metals, single-crystal semiconductors, and polycrystalline
elemental or compound semiconductors within microstructured
silica optical fibers. Because the optical fibers are
constructed and the functional materials are chemically deposited
in distinct and independent steps, the full design flexibilities
of both platforms can now be exploited simultaneously for fiber-integrated
optoelectronic materials and devices. The authors have
also demonstrated the first field-effect transistor inside
the fiber, as well as guiding of 1550nm wavelength infrared
light used today in optical communications. Future applications
that are foreseen include building electronic circuits inside
a fiber, and generating, modulating and detecting light within
a fiber.
Media coverage can be found at:
http://tanzanite.chem.psu.edu/publicity.html
|
