Engineering Professor Wins NSF Award for Nanoscale Research
Structural engineering is defined as the science of extremely large things — battleships, buildings, bridges — but there’s a new group of researchers, led by New Jersey Institute of Technology’s Fatemeh Ahmadpoor, working to understand the structural engineering of extremely tiny things.
If a sheet of copy paper on your desk spontaneously crumpled, it might be time to call Ghostbusters, but if a sheet of a nanoscale structure suddenly crumpled, it would be normal because of the impact of entropic effects from thermal energy. That’s the kind of problem Ahmadpoor is working on, to make such structures predictable, reliable and stable despite entropy.
“These things happen just naturally at nanoscale and that's really interesting. It's not really intuitive or the way we expect to see materials behave at the macro scale. As a mechanical engineer, if I'm given a task to design a device at nanoscale, I have to keep these attributes in mind. I have to predict how the materials and devices respond,” noted Admadpoor, assistant professor of mechanical and industrial engineering.
“The entire field of mechanics is to study the deformations and the forces being applied on solid materials,” Ahmadpoor explained. “It’s a very old field in mechanical engineering. But now that we are in the era of nanotechnology, and we are working with devices that are getting smaller and smaller, going to nanoscale or even atomic level, a lot of things that we've learned in the mechanics field are not applicable. So if as a mechanical engineer I want to design a device at nanoscale, I need some other guidance, some other mechanical design rules. I’m interested to develop those rules.”
She received a $530,000 grant for the prestigious National Science Foundation Faculty Early Career Development Program, commonly known as the career award, from June of this year through May 2028 to develop theoretical and computational models of such problems. Ultimately, she’d like to have her own laboratory and create physical experiments. The result will be journal articles and digital models, which engineers can use in new products for fields such as defense, healthcare and industry.
In scientific terms, “models of plates and shells will be integrated with concepts of statistical mechanics,” her NSF grant abstract states. This will help her understand instability, sensitivity and vibrations, among other properties, of fluctuating membranes.
“These studies are challenging due to nonlinearities, non-traditional boundary conditions and ubiquitous presence of thermal fluctuations and material imperfections,” the abstract continues. “The developed continuum-statistical mechanics platform would be extendable to other small-scale problems including entropy-driven failure mechanisms of nanomaterials, mechanically coupled properties of nanomaterials and active matters in biology.”
Ahmadpoor found her way to these issues when starting her Ph.D. in 2012. Physicists had been studying small scale behavior of materials since the 1970s. “At that time, we didn't even have these devices. We didn't really care. But these physicists were interested, from just a fundamental basic research perspective,” she continued.
“It took me a long time, several years, to first understand what these physicists are saying and somehow translate those concepts into mechanical approaches that can be used by engineers with no background in physics,” she added. Now, she will develop theoretical platforms for mechanics-guided design of nanodevices. For the computational tasks, she’ll use software called LAMMPS, or Large-scale Atomic/Molecular Massively Parallel Simulator, produced by the U.S. government at Sandia National Laboratories. Looking forward, “I want to say, ‘If I introduce random atomic level defects, I want to predict how this nanodevice would behave.’”