FSU physicist awarded collaborative Department of Energy grant to develop models of quantum matter

A Florida State University condensed-matter physicist is part of a team exploring how quantum materials, which are materials that power everything from modern electronics like smartphones to natural processes like photosynthesis, respond in real time to changing environmental factors, such as magnetic fields, light and temperature.

Associate Professor of Physics Hitesh Changlani has earned a $2 million grant from the U.S. Department of Energy, or DOE, with his collaborator Kemp Plumb, an associate professor of physics at Brown University, to model out-of-equilibrium quantum matter using neutron scattering. The goal of this research is to understand how to steer materials toward specific quantum states useful to scientists. Nearly $800,000 of the grant will come to FSU and the National Science Foundation-funded, FSU-headquartered National High Magnetic Field Laboratory, with which Changlani is also affiliated.

“Quantum mechanics is all around you: in your phone, in superconducting materials, in magnets and more,” Changlani said. “There are so many important processes happening at a microscopic level that we have yet to comprehend, and this research will help us better understand how we can create more efficient quantum materials by controlling interacting electrons’ responses.”

Studies on quantum matter often focus on matter’s behavior in an equilibrium state, a condition where all competing forces in a system are balanced. Changlani’s theoretical physics research investigates how non-living systems, like interacting electrons in quantum materials, behave similarly and self-stabilize.

“The field of non-equilibrium physics has achieved a lot of importance over the last 20 years,” Changlani said. “Developments across the field have helped us understand how we can steer quantum materials to desirable states, like superconducting states, so we can use them more efficiently in modern technologies.”

This grant will allow Changlani, a theorist, and Plumb, an experimentalist, to collaborate with the Oak Ridge National Laboratory, or ORNL, in Oak Ridge, Tennessee. FSU is a core university partner of ORNL, the largest DOE science and energy laboratory. There, the team will investigate how nickel-based magnetic pyrochlores, whose unconventional properties the team previously characterized in equilibrium settings, react when they are out of equilibrium with their environment.

“Hitesh has become a leader in our department very early in his career path,” said Paul Cottle, Department of Physics chair. “His collaboration with Brown University shows that he’s reached a new milestone in his scientific development.”

When interacting with other forces like electromagnetism, electrons drop from excited, high-energy states to low-energy states. The team will use an imaging technique called neutron scattering to uncover how electrons in magnetic materials like pyrochlore navigate this state change in response to changing electromagnetic forces.

“If you fracture your arm and look at an X-ray of it every day, you’ll see how your arm is healing,” Changlani said. “We’re using a similar technique by shooting neutrons at a magnetic system evolving slowly enough that we can observe those changes.”

Neutrons that are fired at a material interact with the spin of its electrons and lose energy as they are deflected. Information from the lost energy is used to create real-time images of the arrangement of electron spins. These images are captured in collaboration with ORNL’s Neutron Scattering Division, and Changlani creates simulations using high-performance computing resources at FSU’s Research Computing Center.

“Neutron scattering has illuminated how materials like high-temperature cuprate superconductors, quantum spin liquids and altermagnets, which are relevant to important technologies like quantum computers, power grids and storage devices, work in equilibrium,” Changlani said. “However, using neutron scattering for out-of-equilibrium quantum matter is still relatively uncharted territory, and I’m excited to have the opportunity to model it.”

Changlani and Plumb first met as postdoctoral researchers at Johns Hopkins University in 2016. Since then, they have collaborated several times, including at the 2019 Theory Winter School, hosted by the National MagLab. Changlani is a member of the FSU Quantum Initiative, a multidisciplinary effort to strengthen quantum science research and education at FSU.

To learn more about Changlani’s work and research conducted in the Department of Physics, visit physics.fsu.edu.