Applied Physics Seminar Series

Abstract:

In dilute gases, atomic motion is understood in the real domain (space and time) as atomic collisions and translations, and thermodynamic and transport properties are described in terms of these microscopic events. At the opposite end of the spectrum of matter in solids, these properties are instead commonly described in the reciprocal domain (wavevector and frequency) through phonon quasiparticles. These two seemingly incompatible theoretical frameworks come into direct conflict when describing intermediate forms of matter such as liquids and solid ionic conductors. In this talk, we explore atomic dynamics in liquids and dilute gases through the lens of instantaneous normal modes and show that this framework provides a natural bridge between real- and reciprocal-domain descriptions of thermodynamic and transport properties. This perspective offers a pathway toward a more unified understanding of the complex atomic motion that governs the properties of materials.

More about the Speaker:

Dr. Jaeyun Moon is an assistant professor in the Department of Mechanical and Aerospace Engineering at the University of Florida. He also holds an affiliate appointment in the Department of Materials Science & Engineering. He completed postdoctoral research at Cornell University and Oak Ridge National Laboratory. Dr. Moon earned his B.S. in Mechanical Engineering from the Georgia Institute of Technology and his M.S. and Ph.D. in Mechanical Engineering from the California Institute of Technology. During his doctoral studies, he was awarded the Samsung Fellowship, the Resnick Graduate Fellowship, and the Acosta Fellowship. He is also a recipient of the International Union of Crystallography Young Scientist Award for his research on the thermal properties of glasses. Outside of work, Dr. Moon enjoys cycling, swimming, and hiking.