Transistor laser feels the heat

Researchers at the University of Illinois at Urbana-Champaign have demonstrated the room-temperature operation of a heterojunction bipolar transistor laser, moving it an important step closer to commercialisation. The scientists describe their work in the September 26 issue of the journal Applied Physics Letters.

"We have shown that the transistor laser, even in its early state of development, is capable of room-temperature operation at a speed of three gigahertz," said Nick Holonyak Jr., a John Bardeen Chair Professor of Electrical and Computer Engineering and Physics at Illinois. "We expect the device will operate at much higher speeds when it is more fully developed, as well as play an important role in electronic-photonic integrated circuits."

Room-temperature transistor lasers "could facilitate faster signal processing, large capacity seamless communications, and higher performance electrical and optical integrated circuits," said Milton Feng, the Holonyak Chair Professor of Electrical and Computer Engineering at Illinois. Feng's research on heterojunction bipolar transistors has produced the world's fastest bipolar transistor, a device that operates at a frequency of 600 gigahertz or more, and is a natural platform on which to develop a transistor laser.