A recent development by University of Pittsburgh physicists could eventually lead to molecules being scanned in a manner that slightly resembles imaging screening at airports.
The detector, unveiled in a recent issue of Nano Letters, may possess the ability to chemically identify single molecules using terahertz radiation, a range of light that is far below what the eye can detect.
"Our invention allows lines to be 'written' and 'erased' much in the manner that an Etch A Sketch® toy operates. The only difference is that the smallest feature is a trillion times smaller than the children's toy, able to create conductive lines as narrow as two nanometers,” said study co-author and professor in the Department of Physics and Astronomy within the Kenneth P. Dietrich School of Arts and Sciences, Jeremy Levy.
Terahertz radiation comprises of a wide array of colors that are invisible to the naked eye and are highly useful in identifying particular types of molecules. This kind of radiation is produced and detected with the assistance of an ultrafast laser, a strobe light that turns on and off in less than 30 femtoseconds (a unit of time equal to 10-15-of a second). Terahertz imaging is most frequently found and utilized in airport scanners, yet has been difficult to implement to individual molecules due to a lack of sources and detectors that are able to meet those specific scale requirements.
"We believe it would be possible to isolate and probe single nanostructures and even molecules performing 'terahertz spectroscopy' at the ultimate level of a single molecule. Such resolution will be unprecedented and could be useful for fundamental studies as well as more practical applications,” said Levy.
Levy and his research team are currently in the process of performing spectroscopy of molecules and nanoparticles. The research team wishes to work with a C60, a renowned molecule within the terahertz spectrum, some time within the near future.
The oxide materials used for this research were provided by study coauthor Chang-Beom Eom, Theodore H. Geballe Professor and Harvey D. Spangler Distinguished Professor at the University of Wisconsin-Madison College of Engineering.
Additional collaborators include, from Pitt's Department of Physics and Astronomy, Research Assistant Professor Patrick Irvin, Yanjun Ma (A&S '13G), and Mengchen Huang (A&S '13). Also involved was the University of Wisconsin-Madison's Sangwoo Ryu and Chung Wung Bark.
The research was supported by grants from the United States Air Force Office of Scientific Research and the National Science Foundation.
