Notre Dame terahertz collaboration awarded major DoD grant

Nanowires made of gallium nitride, the material that has the potential to lead a

by Arnie Phifer
June 14, 2011

NOTRE DAME, IN--A group of faculty researchers involved in two of Notre Dame’s strategic research investments—the Center for Nano Science and Technology (NDnano) and the Advanced Diagnostics and Therapeutics initiative—has been awarded a $6.3 million grant from the Department of Defense’s Multidisciplinary Research Initiative (MURI) to develop new electronic devices that operate in the terahertz (THz) range of the electromagnetic spectrum.

Patrick Fay (principal investigator), Debdeep Jena, and Huili (Grace) Xing lead a multi-institutional team—which also includes researchers from The Ohio State University, Johns Hopkins University, and Wright State University—that secured the highly competitive grant for their program to develop novel terahertz devices based on gallium nitride (GaN).

“The terahertz frequency range lies in a region between infrared optics and microwaves,” explains Fay. “The ability to generate, receive, and process signals at terahertz frequencies can have a potentially significant impact on critical areas such as medical sensing, chemical agent screening, and military imaging and communications.”

While scientists have been studying terahertz phenomena in the laboratory for years, the ability to generate high-quality coherent sources has been limited to very low power levels. Moreover, the current sources are difficult to adapt for sensing systems operating outside of the lab, thus limiting the ability to take full advantage of the unique properties of THz frequency signals.

That’s where gallium nitride comes in. GaN is a very robust material that has already been exploited for its optoelectronic properties (it forms the heart of ultra-bright LEDs and the lasers that read Blu-ray Discs).

“We want to understand better the physics of gallium nitride,” says Xing, “and develop novel ways to design GaN-based devices for ultra-high performance applications. The goal is then to incorporate the material into electronics that enable a wide range of new terahertz applications.”

She adds that GaN may form the basis of “the third electronic revolution, after vacuum tubes and silicon.”

The research group receiving the award includes electrical engineers, material scientists, and physicists, each of whom brings different expertise from fields such as semiconductor devices, electromagnetic simulation and design, GaN growth, and high-frequency device and materials characterization.

“The team taking on this challenge is as multifaceted as the problem it’s tackling,” says Jena. “We’re exploring some unconventional, even revolutionary design concepts to realize this vision.”

Last year, Jena and Xing received separate Department of Defense funding—through the Defense Advanced Research Projects Agency—for a project to create new GaN ultraviolet light sources that can be used by soldiers (and eventually civilians) to purify water in the field, further underscoring the opportunities being created by Notre Dame’s gallium nitride research.

Related story: Engineering professors receive MURI grants

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The University of Notre Dame’s Center for Nano Science and Technology (NDnano) is a leading nanotechnology research center. It promotes collaboration between faculty, students, and industry, government, and academic partners to develop new ideas and products on the nano scale.

The University of Notre Dame’s Advanced Diagnostics & Therapeutics initiative is a multi-disciplinary effort to create tools and technologies to combat disease, promote health, and safeguard the environment.