The Nano Mechanic
In Dan Gianola's universe, the Earth is about the size of a marble.
Daniel Gianola is working at the nanoscale, with materials that are about a thousand times smaller than the diameter of a human hair. Using a sophisticated set of electron microscopes and his talent for developing novel ways to manipulate and test samples, Gianola is discovering uncommon properties, such as deformation at or near theoretical strengths, and forging new understandings about the relations between atomic structure and performance of materials at the nanoscale.
"A lot of science is about seeing how far you can go, and exploring extreme outer regions, where distance is measured in light-years," says Gianola, Skirkanich Assistant Professor of Materials Science and Engineering (MSE). "What we're doing is the opposite. We're trying to see what's on the inner edges. What happens when you go below an atom? And how can we, as engineers, exploit that? Can we design new materials with new functionality and new properties?"
Gianola, a mechanical engineer with degrees from the University of Wisconsin-Madison and Johns Hopkins University, arrived at Penn in the summer of 2009. He brought with him innovative techniques and experimental tools that he'd developed during his Ph.D. research and his work as an Alexander von Humboldt postdoctoral fellow in Karlsruhe, Germany. The results of his research into the mechanical behaviors of nanowires and nanocrystalline materials are proving significant to the engineering of small devices such as thin films, integrated circuits, micro- and nanoelectromechanical systems (MEMS and NEMS), and advanced power devices.
At Penn, Gianola is designing and conducting experiments in situ—inside electron microscopes. "It's what we see as a frontier," he says. "We devise a test to stretch something, or pass a current through a sample, or heat it inside the microscope. This allows us to see simultaneously the atomic scale structure, how atoms are packed, and how they're modified by the influence of the test. We want to see those dynamics." The ability to concurrently image and run an experiment—to view and measure shifts in atoms that might cause defects, or to catch the point at which a dynamic behavior manifests itself—is reducing some of the educated guesswork of interpreting results. "It's like having box seats to a baseball game instead of listening to play-by-play action on the radio," Gianola explains. "Now you can watch the action and see what's going on."
In a lab where three hours is the time to beat when it comes to moving five nanowires into position in a microscope, one of Gianola's goals is higher throughput, economizing on materials and time and maximizing the outcome of experiments. He and his group leverage common forces and interactions in unique ways to manipulate nanomaterials.
"It's not gravity, it's not our fingers," Gianola says of the techniques known as self-assembly. "It's letting these natural, or somewhat synthetic forces interact with the material while we have our hands behind our backs. If we're clever enough as engineers, we can figure out just how to design our system so that materials go just where we want them to."
When he's not working on his own experiments, Gianola is in the classroom and the lab with his undergraduate and graduate students. " In addition to an upper-level class on the mechanical behavior of materials, Gianola teaches an undergraduate nanoscale materials lab, centered around experiments that cover the fundamental concepts of materials science. "I try to keep one foot in the lab," Gianola explains, "because I love it and because my students run into so many challenges along the way. If I'm too distant from it, I don't think I'd be an effective advisor for them."
View the full article in Penn Engineering Magazine: "The Nano Mechanic" by Catherine Von Elm.