Terahertz waves can "see" bioagents from 20 meters away

Researchers with Rensselaer Polytechnic Institute say they have made a breakthrough in detecting hidden chemical and biological agents from up to 20 meters away.

Xi-Cheng Zhang, director of the Center for Terahertz Research at Rensselaer, told physorg.com that the new optical sensing system, which uses terahertz wave technology, has great potential for homeland security uses because it literally sees through clothing and packing materials.

Zhang said that terahertz waves make up a large part of the electromagnetic spectrum between infrared and microwave bands. He said this is a huge plus because these bands have sensor capabilities that go far beyond that of exiting technologies like X-rays and microwaves.

“The potential of THz wave remote sensing has been recognized for years, but practical application has been blocked by the fact that ambient moisture interferes with wave transmission,” Zhang told physorg.com.

The new system will be described in detail in a paper he wrote that will appear in an upcoming edition of the journal Nature Photonics.

Zhang said the thwarted Christmas Eve bombing attempt aboard a Delta airline created an interest in further development of THz remote sensing, especially from Homeland Security and the Defense Department, which have funded much of the Rensselaer research.

“I think I can predict that, within a few years, the THz science and technology will become more available and ready for industrial and defense-related use,” Zhang said.