A new Department of Energy grant will support a University of Iowa engineering professor developing a high-powered laser with benefits ranging from national security to health care diagnostics.

Fatima Toor is at the center of the project funded through the competitive Laboratory Directed Research and Development (LDRD) Program. LDRD was established by Congress at the Department of Energy national laboratories in 1991. Toor is an associate professor of electrical and computer engineering, Lowell G. Battershell Chair in Laser Engineering and faculty affiliate at the Iowa Technology Institute.

The proposal calls for using a quantum cascade laser (QCL), which was originally designed for infrared light, to create terahertz (THz) radiation at a frequency of 1.2 THz. The proposed THz energy source offers unprecedented power that does not exist today, Toor said.

The team members at LLNL, UI, and SRI International will tweak the waveguide design of the QCL to keep the light mode confinement high while minimizing energy loss. This design is expected to lower the threshold current of the proposed THz QCL while also increasing the power output.

The project could unlock new and improved applications due to the more powerful laser.

THz radiation can pass through materials like foam and human tissue because of a principle called Rayleigh scattering, which explains how light interacts with small particles.

This could help sensors better detect dangerous chemicals, toxic gases, or controlled substances. Doctors could use the technology for non-invasive health checks on patients.

“Development of high-power THz sources will benefit national security in the areas of advanced chemicals sensors for energetic materials and controlled substances,” Toor said. "The commercial sector will benefit from the crucial, game-changing THz technology development in the areas of detection of toxic gases and non-invasive health diagnostics and imaging.”

Toor is leading the Iowa portion of the project, which has received $150,000 in funding over one year. Collaborators include Natalie Kostinski, Brian Poole, Dong-Xia Qu all of Lawrence Livermore National Lab and Zane Shellenbarger of SRI International.