Turning to Terahertz for Chemical Detection Take a silicon wafer, add a bit of boron in just the right amount, place the wafer inside a cellphone-sized laser-style pointer device that uses semiconductor nanostructures and voilà: a handheld machine that harnesses terahertz frequencies to find cancers in the human body or determine the chemical makeup of hazardous waste spills. A team at the University of Delaware is perfecting their terahertz findings, writes Jean Thilmany. Somewhere between light waves and radio waves lays a relatively unexplored part of the electromagnetic spectrum — the terahertz frequencies that University of Delaware Professor James Kolodzey calls the final frontier in the study of electromagnetic waves. He's exploring ways to put those frequencies to practical, everyday use in the medical and hazardous waste industries, among others. Terahertz frequencies are 1000 times higher than microwave frequencies and 100 to 1000 lower than visible light. Because terahertz frequencies are easily absorbed by moisture in the atmosphere, they don't travel long distances; for that reason they haven't garnered the study given microwave frequencies used in cellphones and ovens. For years, researchers thought terahertz frequencies had no modern-day use. But Kolodzey, an electrical and computer engineering professor realized terahertz could be of great value for close-range applications. "The region we call terahertz interacts with molecules and chemicals and biological agents in the air; there are interesting resonances and dispersions," Kolodzey said. "That makes them ideal for sensing the chemical composition of the environment. In this day and age, that's practical for analyzing and measuring." the Alchemist: 5/14/03 The Alchemist, 2/03 Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.