Silicon photonics
INTEGRATED APPROACH: The focus is on ways to sillconise photonics now. Photo: H.Vibhu.
THE FIRST continuous wave all-silicon laser was developed by the researches at Intel using a physical property called the Raman Effect. The experimental device was built using the existing standard CMOS high-volume manufacturing processes.
A novel diode-like structure (technically called a PIN - P-type/Intrinsic/N-type device) was incorporated into the silicon cavity laser. This solved the "two photon absorption" problem that caused early versions of the device to only achieve lasing for an infinitesimal fraction of a second before shutting off.
Like the first laser developed in 1960, this device uses an external source (a laser) to supply the initial energy. The PIN device combined with the Raman Effect produces a continuous laser beam at a new wavelength. The breakthrough device could lead to such practical applications as optical amplifiers, lasers, wavelength converters, and new kinds of lossless optical devices. A low-cost all-silicon Raman laser could inspire innovation in the development of new medical, sensor, and spectroscopy devices.
Greater bandwidth
Photonics offers much greater bandwidth than traditional copper networks and can carry multiple signals simultaneously without interference. Today's commercial photonic devices are made from exotic materials such as indium phosphide and gallium arsenide and their high cost limits the use of traditional photonic devices.
The focus is on the ways to "siliconize" photonics and to make integrated, inexpensive photonic devices out of silicon instead of the exotic materials used today. By demonstrating how optical modulators can be made out of silicon, researchers have removed a significant cost barrier in photonics. The next step is integrating entire photonic devices on a chip with digital intelligence. This should pave the way to produce photonics products based on silicon.
Ramakrishna. K & Rajendra Prasad. S.P,
FCET, Chevella
Printer friendly
page
Send this article to Friends by
E-Mail
Education Plus
Karnataka
Chennai
Coimbatore
Hyderabad
Madurai
Tiruchirapalli
Vijayawada
Visakhapatnam
