Progress at the Speed of Light

Every second, untold trillions of light pulses carry voice and data traffic through the worldwide telecommunications network, yet the telephones, computers, and other devices at the end of the line are, for the most part, electronic.  Newly appointed electrical engineering professor Joe C. Campbell was instrumental in devising that critical component, called a high-speed avalanche photodiode, that changes photonic signals into electronic signals extremely quickly, reliably, and with very little noise or distortion.  This was no easy task.  For this achievement, Campbell was named to the National Academy of Engineering, the highest honor in the engineering profession.

This year, Campbell joined the University as the Lucien Carr III Professor of Engineering and Applied Science at the University of Virginia in the Charles L. Brown Department of Electrical and Computer Engineering.  His appointment is the first in a Board of Visitors' initiative to raise the standing of science and engineering at the University by bringing 10 researchers of National Academy caliber to the University.

Campbell's appointment illuminates the transformative potential of this initiative.  Researchers of this stature bring a host of funded research projects with them when they move. Campbell is bringing a $3 million laboratory, an outstanding group of graduate students and postdoctoral researchers, and a host of cutting-edge projects related to photon detectors and optical sensors.  Campbell's presence will provide abundant opportunity for collaboration with existing faculty and help attract high-quality faculty and graduate students to the University.

Currently, Campbell has a number of projects under way.  He is developing very sensitive photodetectors that work in conjunction with a laser source to pinpoint airborne biological agents.  The detectors can pick up their faint optical signature revealed by reflected laser light and set off an alarm.  These detectors can be used in buildings and public spaces as well as on the battlefield.

Campbell is also working on a next-generation avalanche photodiode that would work at many times the speed of current devices, an effort that has required pioneering work in semiconductor physics to identify sources of noise that increase with speed.  Currently, avalanche photodiodes operate at 10 gigabits a second.  The devices under development in Campbell's lab will communicate more than four times faster.

In addition, Campbell is collaborating on a project to create a new way of detecting infrared radiation.  His approach is to use quantum dots, minute pyramid-shaped collections of semiconductors that allow electrons to be uniquely trapped and measured.  This new technology has the potential of displacing the inefficient mercury cadmium telluride sensors critical to night-vision goggles, military tracking devices, environmental monitors and some space telescopes.

Now that Campbell has moved to Charlottesville, the University will be the focal point of these projects and others that Campbell is working on-and Campbell is excited to be here.  “I've long known that U.Va. is a special place and a first-rate university,” Campbell said of his reasons for coming to U.Va. “What particularly impressed me is the University's vision for the future in research, the leadership at the University and their energetic initiatives to move up in the rankings. I want to be a part of that.”