Materials Science Research Lecture
***Refreshments at 3:45pm in Noyes lobby
Abstract:
Small-angle neutron scattering (SANS) is a versatile technique used to investigate structural features on length scales ranging from 1 nm to nearly 1 μm. This seminar will provide a foundational overview of the method, beginning with essential SANS analytical frameworks such as Guinier and Porod analysis for characterizing particle size and surface morphology. We will then explore the power of contrast variation through practical examples, including the isolation of multi-component systems using contrast-matched silica in H2O/D2O mixtures. The talk will further examine the application of SANS to complex magnetism, specifically focusing on the magnetic diffraction of Nd-based systems and the realization of magnetic skyrmions in thin films. Finally, I will discuss the extraction of hydrogen and the nuances of data interpretation, highlighting why careful consideration of sample environment and background subtraction is critical for drawing accurate scientific conclusions in neutron scattering experiments.
More about the Speaker:
Lisa DeBeer-Schmitt is a Senior R&D Staff member and the GP-SANS Instrument Scientist at the High Flux Isotope Reactor (HFIR), Oak Ridge National Laboratory (ORNL). She holds a B.S. in Physics from Georgia Southern University and a Ph.D. from the University of Notre Dame, where her doctoral research focused on flux-line lattices in unconventional superconductors. Following a postdoctoral fellowship at the GP-SANS beamline, she joined the ORNL staff in 2011 and has since held various leadership and technical roles, including Team Lead for SNS Sample Environment and membership on the SEQUOIA team.
As a specialist in small-angle neutron scattering (SANS), Dr. DeBeer-Schmitt focuses on magnetic diffraction at long length scales (nanometers) and the development of new methodologies to address complex scientific inquiries. Her research portfolio includes over 100 publications reflecting a broad range of expertise in neutron scattering, with primary interests in skyrmion systems, 3D SANS tomography, and the characterization of engineering materials, such as high-entropy alloys and reactor-based materials. Her current development work includes advancing facility capabilities through robot-assisted sample changers for highly irradiated materials within magnetic fields.
Beyond her research, she serves as an Executive Committee member for the Southeastern Section of the American Physical Society (SESAPS). Her professional service also includes editorial board roles for Frontiers in Physics: Condensed Matter and IEEE Magnetic Letters, as well as five years of instructional contributions to the ORNL/Argonne Neutron and X-ray School