http://newsfromrussia.com/science/2005/02/18/58317.html
Intel creates the first continuous silicon laser beam 02:17 2005-02-18 Researchers from Intel Corp. have announced that they have created the first continuous laser beam using silicon components that may signify advances in communications and medicine. Such a laser could make high-bandwidth, light-based communication feasible for not only the connections between computers but also the links between components inside PCs. It also could slash the cost of lasers used in defense, medicine and other industries, reports Xinhua News. In a paper to be published today in the journal Nature, Intel's Photonics Technology Laboratory reports a way to overcome the primary hurdle to using silicon as a medium for laser light, an effect in which electrons freed by the energy of passing photons absorb the light as it passes through. Researchers at the world's largest maker of microchips overcame that problem, called two-photon absorption, by using a technique from the world of semiconductors. It created positive and negative regions around the path of the laser light, which "vacuum" away electrons and provide a clear road for the laser. Bahram Jalali, a professor of electrical engineering at the University of California in Los Angeles who has also done work with silicon lasers, said Intel's laser holds promise as the basis for defense applications, as in infrared jamming devices to defend against heat-seeking missiles, informs the Houston Chronicle. According to the Information Week, Intel claims to have made another breakthrough in the arena. "Because of the nonlinear optical loss associated with two-photon absorption (TPA)-induced free carrier absorption (FCA), until now lasing has been limited to pulse operation," according to Intel. "Specifically, we show that TPA-induced FCA in silicon can be significantly reduced by introducing a reversed-biased p-i-n diode embedded in a silicon waveguide." The laser is built around a low loss SOI rib waveguide, whose facets are coated with multilayer dielectric films. "The silicon rib waveguide is fabricated on the surface of an undoped SOI substrate using standard photolithographic patterning and reactive ion etching techniques," according to Intel's description in Nature. "The p-i-n structure was formed by implanting boron and phosphorous in the slab on either side of the rib waveguide." JB [Non-text portions of this message have been removed] ------------------------ Yahoo! Groups Sponsor --------------------~--> What would our lives be like without music, dance, and theater? Donate or volunteer in the arts today at Network for Good! http://us.click.yahoo.com/pkgkPB/SOnJAA/Zx0JAA/uTGrlB/TM --------------------------------------------------------------------~-> Post message: [EMAIL PROTECTED] Subscribe : [EMAIL PROTECTED] Unsubscribe : [EMAIL PROTECTED] List owner : [EMAIL PROTECTED] Homepage : http://proletar.8m.com/ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/proletar/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
