A group of researches from the University of Maryland, Monash University, Australia and US Naval Research Laboratory have created a detector which can scan beyond bodies; walls and other objects that are invisible to human eye.
The scientists have made use of graphene which is a two dimensional form of carbon and one atom thick. A prototype detector which the team created can see broad band of wavelengths. The prototype could also see the Terahertz wave which have exciting potential application but are not visible to the human eye. The long and low wavelengths of Terahertz light waves fall between microwaves and infrared waves and can pass through opaque materials such as skin, plastics, clothing and cardboard, the researchers said.
Lead author Xinghan Cai, a University of Maryland (UMD) physics graduate student, said, “A detector like the prototype could find applications in emerging terahertz fields such as mobile communications, medical imaging, chemical sensing, night vision and security.”
Professor Michael Fuhrer, School of Physics at Monash, said the research could lead to a generation of light detectors that could see below the surface of walls and other objects.
“We have demonstrated light detection from terahertz to near-infrared frequencies, a range about 100 times larger than the visible spectrum,” Professor Fuhrer said.
“Detection of infrared and terahertz light has numerous uses, from chemical analysis to night vision goggles, and body scanners used in airport security.”
The concept behind the detector is simple, says UMD Physics Professor Dennis Drew. “Light is absorbed by the electrons in graphene, which heat up but don’t lose their energy easily. So they remain hot while the carbon atomic lattice remains cold.”
These detectors have to be kept extremely cold to maintain sensitivity. The new room temperature detector, developed by the UMD team and colleagues at the US Naval Research Lab and Monash University, Australia, gets around these problems by using graphene, a single layer of interconnected carbon atoms. The research was published in the journal Nature Nanotechnology.