Photonics Pioneer to Lead UTDallas Engineering
DALLAS, Oct. 30, 2013 — Dr. James Coleman, a leader in the development and application of semiconductor lasers and photonic devices, recently joined the University of Texas at Dallas to lead its electrical engineering department, the university said.
An endowed professor of electrical engineering and materials science and engineering at The University of Illinois at Urbana-Champaign, Coleman was a pioneer in metallorganic chemical vapor deposition (MOCVD), a process that creates complex semiconductor structures and that is widely used today in photonics manufacturing.
At UT Dallas, where he holds the Erik Jonsson School of Engineering and Computer Science Distinguished Chair, Coleman will continue his research on strained layer lasers, self-assembled and patterned quantum dots, and low-threshold and high-power single-mode-index-guided lasers and arrays.
Coleman holds nine US patents and has authored more than 425 papers. He was elected to the National Academy of Engineering in 2012 for his contributions to semiconductor lasers and photonic materials. He is also a fellow of the Institute of Electrical and Electronics Engineers (IEEE), the Optical Society (OSA), the American Physical Society, SPIE and the American Association for the Advancement of Science (AAAS). He has received the Distinguished Lecturer Award and William Streifer Award from the IEEE Photonics Society; the David Sarnoff Award from IEEE; the Nick Holonyak Jr. Award from OSA; and the John Tyndall Award, presented jointly by the IEEE Photonics Society and OSA.
“We are extremely fortunate and pleased to have an internationally renowned researcher and leader like Jim Coleman come to UT Dallas to head our electrical engineering department,” said Dr. Mark W. Spong, dean of the Jonsson School. “Jim brings an enormous wealth of talent and experience from a top-five engineering school, and the timing could not be better to help the Jonsson School reach our Tier One goals.”
In the early 1990s, Coleman’s group challenged the traditional paradigm about the practicalities of using layers of materials of different physical sizes, known as strained layers, in semiconductor devices. Conventional wisdom was that devices made of these layers would be impractical because, under stress, these strained layers would bend and fail.
“What we found, to our surprise, was that lasers with these layers could have a small amount of strain and interesting properties, and they did not fail; in fact, quite contrary, they lasted longer,” Coleman said. “This finding opened a new class of structures that makes better and different lasers that were not previously practical.”
Strained layers are used in everyday electronic devices, such as CD and DVD players.
Coleman earned his bachelor’s, master’s and doctoral degrees in electrical engineering from the University of Illinois in the 1970s. At that time, semiconductor lasers were only about a decade old and impractical. The possibility of future applications and the combination of topics that interested Coleman – magnetics, semiconductors, quantum mechanics, materials and devices – drew his attention to the field.
He spent several years working for Bell Laboratories and Rockwell International, where he helped demonstrate the effectiveness of the MOCVD process to make lasers, solar cells and photodetectors with better performance characteristics.
“I spend a lot of time telling students that there is a world of difference between interesting and useful,” Coleman said. “You can be interested in something, but you have to ultimately be concerned about what is useful.”
He then went back to UIUC as a professor, where he brought his experience making semiconductors using MOCVD, which then was still a new process. His work has led to wider applications of semiconductor lasers, and manufacture and production on a more economical and feasible scale. His research refined not only semiconductor devices, but also the materials used to make them.
"Working on semiconductors is a two-part problem: the device and the materials," he said. "If you found something interesting about materials, then you had to find a way to get it into a device. I have always enjoyed that push and pull between materials and devices. Which one is pushing and which one is pulling is not always obvious."
For more information, visit: www.utdallas.edu
- quantum dots
- Also known as QDs. Nanocrystals of semiconductor materials that fluoresce when excited by external light sources, primarily in narrow visible and near-infrared regions; they are commonly used as alternatives to organic dyes.
- quantum mechanics
- The science of all complex elements of atomic and molecular spectra, and the interaction of radiation and matter.
- semiconductor laser
- A semiconductor material which is designed and grown for the efficient production of short wavelength stimulated emission through high gain as well as low internal losses. Materials with band gap energies which emit radiation efficiently within the desired wavelength region are used. Diodes may emit vertically in relation to the laser material junction in a VCSEL configuration or horizontally in an edge emitting configuration.
Synonymous with laser diode. Sometimes used...
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