Scientists break light modulation record; develop fastest LED

June 23, 2009--Researchers at the University of Illinois at Urbana-Champaign (Champaign, IL) have constructed a light-emitting transistor that has set a new record with a signal-processing modulation speed of 4.3 gigahertz (GHz). By internally connecting the base and collector of this light-emitting transistor, they created a new form of light-emitting diode (LED) that modulates at up to 7 gigahertz, breaking a previously announced record of 3.6 GHz for a plasmonic LED.

June 23, 2009--Researchers at the University of Illinois at Urbana-Champaign (Champaign, IL) have constructed a light-emitting transistor that has set a new record with a signal-processing modulation speed of 4.3 gigahertz (GHz). By internally connecting the base and collector of this light-emitting transistor, they created a new form of light-emitting diode (LED) that modulates at up to 7 gigahertz, breaking a previously announced record of 3.6 GHz for a plasmonic LED (see "Plasmonic LED approaches 10 GHz modulation speed").

In a pair of papers published in the June 15 issue of Applied Physics Letters, researchers at the University of Illinois and at University of Illinois licensee Quantum Electro Opto Systems in Melaka, Malaysia, report the fabrication and testing of the new high-speed light-emitting transistor and the new "tilted-charge" light-emitting diode.

"Simple in design and construction, the tilted-charge light-emitting diode offers an attractive alternative for use in high-speed signal processing, optical communication systems and integrated optoelectronics," said Nick Holonyak Jr., a John Bardeen Chair Professor of Electrical and Computer Engineering and Physics at Illinois, and a co-author of both papers.

For more information, go to news.illinois.edu/news/09/0615speed.html.

--Posted by Gail Overton, gailo@pennwell.com; www.laserfocusworld.com.

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