Students "Surf" for Graphene at NIST
For Immediate Release: September 1, 2008
Contact: John Unguris
More than 120 science, mathematics and engineering college students and recent college graduates were given a chance to ride the next wave in cutting-edge science as part of the 2008 Summer Undergraduate Research Fellowship (SURF) program in Gaithersburg, Md. Supported by the National Institute of Standards and Technology (NIST), the National Science Foundation, and participating colleges and universities, the program provided students with the opportunity to perform meaningful research in state-of-the-art laboratories along with world-class experts.
As a national research agency, NIST gives students access to equipment and materials that cannot be found in typical university settings. For example, one group of students signed on to be a part of NIST’s graphene project, an agency-wide effort to produce, characterize, and manufacture devices based on this unique and promising carbon structure.
Michael Chang of Pennsylvania State University and his advisor, NIST physicist David Newell, focused on the fabrication of a graphene-based device to measure the quantum Hall effect. This quantum phenomenon could yield far more accurate measurements of electrical resistance, but the scarcity of high-quality measurement devices and other factors put access to an accurate electrical resistance standard beyond the reach of most laboratories.
Jonathan Lidga of Cornell University, with his advisor, NIST physicist Joe Stroscio (and fellow SURFer Matt Chang), investigated mechanical exfoliation to produce graphene samples. The team then analyzed those samples with a scanning tunneling microscope to uncover the underlying physics of electrons traveling in graphene.
Paul Fuentes-Martinez focused on characterizing the optical and electrical properties of graphene ribbons. Fuentes-Martinez and NIST materials research engineer Jan Obrzut also experimented with chemical techniques to augment the mechanical exfoliation process and ultracentrifugation to separate the different sizes of graphite flakes and isolate the graphene ribbons.
Tessa Johnson, working with NIST physicists Angela Hight Walker and Jeff Simpson, used a laser-based measurement technique known as Raman spectroscopy to explore the underlying physics of graphene and provide the definitive answer to the other teams whether their efforts to obtain a single graphene layer had been successful.