Three faculty members from Penn State have been elected as Fellows of the American Physical Society (APS), the world’s largest organization dedicated to physics. The new cohort of fellows includes Penn State’s Anna Stasto, professor of physics, Chaoxing Liu, professor of physics, and Adri van Duin, distinguished professor of mechanical engineering.
The APS Fellowship Program recognizes members who have made advances in knowledge through original research and publication, have made significant and innovative contributions in the application of physics to science and technology, or who have made significant contributions to the teaching of physics or to service opportunities and activities of the society, according to the APS website. Each year the society elects no more than one-half of one percent of its then-current membership to the status of Fellow.
Stasto and Liu are both from the Eberly College of Science.
“I am thrilled that Anna and Chaoxing are being recognized with the honor,” said Mauricio Terrones, the George A. and Margaret M. Downsbrough Department Head of Physics, Evan Pugh University Professor, and professor of chemistry and of materials science and engineering. “We are extremely lucky and proud to have scientists of their caliber in the department. Their election as APS Fellows could not be more deserved.”
Mary Frecker, department head and professor of mechanical engineering, Riess Chair of Engineering and director of the Penn State Center for Biodevices, expressed similar sentiments regarding van Duin.
“Professor van Duin is one of the world’s leading experts in molecular dynamics simulations,” said Frecker. “It is wonderful to see his considerable research contributions being recognized by the American Physical Society.”
Stasto, professor of physics, was elected for outstanding contributions to quantum chromodynamics — the theory that underlies the strong force in physics, which binds the fundamental particles known as quarks into protons, neutrons, and other particles — at high energies and to the scientific case for future electron-ion colliders.
Stasto studies particle physics, focusing, in particular, on the theory of strong interactions and on astroparticle and neutrino physics. She is especially interested in investigating the high-energy limit of quantum chromodynamics, where new phenomena related to the large densities of quarks and gluons are expected to be observed. In the past, she conducted research related to the so-called deep-inelastic scattering of electrons on protons, a process that was investigated experimentally at the Hadron Electron Ring Accelerator collider in Germany. The results of her theoretical analyses have been applied successfully to a variety of subjects, including structure-function studies of protons; the production of heavy quarks; and the production of jets of particles. She also has studied the mechanisms of the production of neutrinos, which are very light particles with no charge, and she has investigated the propagation of neutrinos through the Earth. She also has been active in developing the scientific case for future Electron-Ion colliders.
Stasto received an Outstanding Junior Investigator award in the field of nuclear physics presented by the U.S. Department of Energy and also received an Alfred P. Sloan Research Fellowship in recognition of her work as a young scientist engaged in cutting-edge research, both in 2009.
Prior to joining Penn State as an assistant professor in 2008, Stasto was a research associate at Penn State from 2006 to 2008. She was a research associate at Brookhaven National Laboratory from 2004 to 2006, and she was a postdoctoral fellow at the German Electron Synchrotron (DESY) in Hamburg, Germany from 2002 to 2004. Stasto earned a master's degree in physics at the Jagiellonian University in Poland in 1996 and a joint Ph.D. in theoretical physics at the Polish Academy of Science and the University of Durham in the United Kingdom in 1999. She received a habilitation degree in theoretical physics from the Polish Academy of Science in 2005.
Liu, professor of physics, was elected for his contributions to theoretical studies of topological insulators — a class of quantum materials in which electric currents flow through the surfaces — and the quantum anomalous Hall effect — a phenomenon where current does not lose energy as it travels along a material’s edge.
Liu is a theorist in condensed matter physics whose current research focuses on a large variety of topological states of matter, including topological insulators, the quantum anomalous Hall state, topological crystalline insulators, and topological superconductors, and exploring exotic physical phenomena in these materials. In particular, he is interested in the relationship between symmetry and topological states, the interaction effect and topological and geometric effects in topological materials. Liu’s group combines theoretical studies with advanced computational approaches and collaborates closely with experimental groups. He is also interested in searching for new materials with exotic properties that may have applications in electronic devices.
Before joining Penn State’s Eberly College of Science, Liu was a postdoctoral researcher with an Alexander von Humboldt Fellowship at the University of Wuerzburg in Germany. He also has served as a visiting researcher at both Stanford University and Hong Kong University in China. Liu received a doctoral degree in physics and a bachelor’s degree in fundamental science from Tsinghua University in China in 2009 and 2003, respectively.
Adri van Duin
Van Duin, distinguished professor of mechanical engineering, was elected for inventing and advancing the reactive force field (ReaxFF) reactive potentials — a powerful computational tool for exploring, developing and optimizing material properties at the atomistic scale that have significantly advanced the field of classical reactive atomistic simulations and bridged the gap between simulation and experiment.
Van Duin is a prominent expert in large-scale atomistic modeling of a wide range of materials. The ReaxFF method that he invented has been used by scientists around the world in more than 1,000 peer-reviewed publications and has been cited more than 50,000 times.
ReaxFF provides a computationally efficient alternative for simulations using the principles of quantum mechanics — which are highly accurate, but also highly computationally intensive. The framework of ReaxFF allows for more practical simulations of the molecular dynamics found in chemically reactive materials and molecules. Equipped with this knowledge, researchers can better understand the materials they are studying on the nanoscale and ultimately optimize their use.
The ReaxFF method has provided insights into many fields, including combustion, materials and biomaterials, polymers, batteries and fuel cells. Van Duin is currently pursuing a project using ReaxFF centered on additive manufacturing, commonly referred to as 3D printing. In that project, van Duin used ReaxFF to study and optimize the interactions between chromium-oxide nanoparticles and a type of binding solution, essentially the “glue” holding the nanoparticles together. By digging into these interactions on the nanoscale, the researchers hope to ultimately build stronger 3D-printed components.
Van Duin earned his doctorandus, a degree comparable to a bachelor’s degree, at the University of Amsterdam and a doctorate at the Delft University of Technology in the Netherlands, followed by postdoctoral appointments at the University of Newcastle upon Tyne in the United Kingdom and the California Institute of Technology. He holds courtesy appointments at Penn State in chemistry, chemical engineering, materials science and engineering, engineering science and mechanics. Van Duin is also co-founder and chief technology officer of RxFF_Consulting.LLC, a consulting company working in the field of ReaxFF training and applications.