The National Science Foundation awarded Prof. Farhan Rana, electrical and computer engineering, a $400,000 grant for his teaching and research work at Cornell. The NSF’s Faculty Early Career Development Program supports young professors who successfully integrate education and research.
Rana won the five-year award for his work with devices that emit very short pulses of laser light, which have important applications in medical imaging, communications and studying molecular interactions. Currently, such pulses are produced by bulky machines that cover a large table and require elaborate cooling systems. Rana aims to improve semiconductor lasers, which fit onto a microchip and harness quantum mechanics to produce similar pulses.
Existing semiconductor lasers have been unable to match the speed or energy output of the larger table-top versions, but Rana’s work aims to close the gap.
“Our goal is to make a semiconductor laser on a chip — which would be maybe less than one millimeter square — that would deliver the same type of pulses that this big thing can do,” Rana said. “We just started the research in this direction.”
He said he will spend the grant on lab facilities, graduate student funding and equipment for his courses. The award is intended for untenured professors early in their careers, such as Rana. He came to Cornell last year, immediately following his doctoral work at Massachusetts Institute of Technology.
“I finished my Ph.D. thesis and I took a plane and landed at Ithaca airport,” he said.
According to Prof. Lester Eastman, electrical and computer engineering, Rana was up against difficult competition for the NSF grant. “These awards are made for young people who show a lot of progress to support them for a couple years and get them rolling,” he said.
But during his year at Cornell, Rana satisfied both the research and education criteria of the grant. He developed two successful new courses that introduce advanced electrical engineering students to his research area. ECE 531, which debuted last semester, won the highest student ratings in its department according to Rana.
After taking the course, Jahan Dawlaty grad became interested enough to embark on a research project with Rana. “He is a very good lecturer, very well-organized and clear,” he said. “It was probably the largest amount of material that I gathered from any course in one semester.”
Rana’s current course offering, ECE 532, is garnering similar student reactions. “It’s one of the most challenging classes I’ve taken but it’s taught very well,” said Martin Schubert ’04, an ECE student. “The professor definitely knows his material.”
The semiconductor laser research, although still in the experimental stages, has also quickly produced results. Rana said his design might create pulses of light as brief as 50 femtoseconds, about 100 times shorter than current semiconductor lasers. A femtosecond is 10 to the negative 15 seconds — in comparison, the fastest computer processors today take several hundred thousand femtoseconds to execute the simplest instructions.
“It shouldn’t cost more than $1,000 [to mass-produce],” Rana said of the design. “There are all these universities that are dying to get big lasers” but are unable to afford the six-figure price of the table-top devices, he said.
The semiconductor lasers are built upon a phenomenon known as quantum dots, which Rana describes as small clusters of material “which tend to perform like single atoms.” Tiny structures with the right shape can elicit specific behavior from electrons and photons in the semiconductor.
“You tailor the electrons and you tailor the photons to get the interaction that you want,” Rana said. “It’s the ability to sculpt it at that scale that gives the advantage.”
“It requires techniques which have been developed over the last 10 to 15 years across several different disciplines,” he said. “You have to combine results