Peter Jiang. Image credit: Carlos Jones, ORNL
Peter Jiang has been captivated by physics since his childhood in China.
“I’ve always been interested in physical phenomena. Why is there a rainbow out there? Why does it have different colors? What makes the waves in the pond? When you throw a stone in the pond, why do the waves fluctuate up and down?” Jiang said. “All those small things got me interested in physics.”
Jiang went on to study physics at Nanjing University in China, where he received his bachelor’s degree before earning a master’s and a doctorate in physics from Indiana University at Bloomington. He came to ORNL as a postdoctoral researcher and now is a staff scientist in the Neutron Technologies Division, where he’s part of a group that develops neutron polarization techniques.
Using ORNL’s High Flux Isotope Reactor and Spallation Neutron Source, Jiang is developing a device that can fully control neutron beam polarization — based on the spin of neutrons — and analyze complex magnetic structures. The development of an advanced spherical neutron polarimetry method could reveal new knowledge in complex magnetic materials that traditional methods have been unable to provide. Advancing research into quantum materials, for instance, requires a deeper understanding of magnetism.
“Spherical neutron polarimetry enables us to map the full picture of the neutron polarization vector during the scattering process,” Jiang said. “This work will enhance our neutron facilities because we’re developing the most advanced techniques in the world.”
Jiang first began working in neutron scattering with his advisor at Indiana University’s Low Energy Neutron Source. He said that working with world-class instruments at HFIR and SNS drives him to continue to expand his knowledge.
“Physics is a fascinating world to me. There is so much that is unknown. You never know when the theoretical world and the experimental world will connect,” he said. “New discoveries can be anywhere.”
The first step in his project is to deploy the polarimetry technique within several instruments at HFIR. Next, the capability will be expanded to SNS, which will be a unique challenge, as spherical neutron polarimetry has never been applied on a time-of-flight instrument — that is, one that collects measurements based on how long an object, particle or wave takes to travel a distance through a medium.
“The instruments are always evolving, and the need for better technique is always there. This keeps me going,” Jiang said. “I want to see what using this new technique can do, what kind of things I can achieve, what kind of new science I can do.”
