UArizona Receives $500K for THz Imager

The University of Arizona College of Engineering has received half a million dollars to develop a unique terahertz imaging instrument. The imager will generate terahertz emissions and analyze how spectra in this range are absorbed and reflected by various materials, such as cell tissues and chemical compounds.

The National Science Foundation made the $530,000 award under its Major Research Instrumentation Program. The university expects the instrument to enable scientists and engineers to expand the frontiers of research in areas such as medical imaging of tumors and pathogens, detection of specific chemicals such as explosives, and the study of metamaterials.

The principal investigator for the three-year project, Richard Ziolkowski, also expects the imager to attract high-tech industries and high-caliber researchers. “It will be a unique instrument in an area that is really starting to grow,” he said. “There are jobs now being created in the terahertz area because people are interested in systems such these imaging devices.”

Although terahertz radiation can penetrate many different materials, including clothing, but not metal, it does not damage cell tissue or DNA as x-rays do. Many of the imagers in airports use terahertz waves, for example. “You get some depth of penetration with terahertz, for example into skin and through clothes,” Ziolkowski said.

One possible application for a terahertz spectral imager is in skin cancer surgery. Another is detecting the presence of disease-causing pathogens such as bacteria and viruses in cells. Product control in the pharmaceutical industry could also benefit from terahertz spectral imaging. “A lot of pills now are time-release, and the thickness of the capsules is important for that time release,” Ziolkowski said. “You can actually see the thickness of the pill casings with terahertz.” He added that quality-control engineers also could examine computer chips and electronic circuits the same way to determine whether there are breaks in the circuits or whether layers and other components are the right depth.

Ziolkowski also expects interest from security agencies because various kinds of explosives have their own terahertz signatures. Thanks to the uniqueness of spectral signatures, the list of applications for a terahertz imager is virtually limitless. One application area is metamaterials, which are engineered materials with unique properties desired for specific physics and engineering applications.

Some of the metamaterials being researched by Ziolkowski, for example, will be integrated into the imager because of the way they emit terahertz waves when hit by pulses of laser light. The objective is to create an efficient and reliable terahertz beam that can be directed into the materials under investigation.

“The metamaterials transform optical pulses into terahertz signals,” Ziolkowski said. “Laser light comes in, strikes the metamaterial structure, and out come nice parallel, well-defined beams of terahertz.”

For more information, visit: www.arizona.edu