seed projects

Jong Seok Jeong: Measuring Phonon Transfer Across the Interfaces Between Two Crystals at the Atomic Scale and Estabilishing Such Capacity

This project targets a new direction in analytical scanning transmission electron microscopy, which is the demonstration and utilization of vibrational spectroscopy in the electron microscope at the atomic scale. One topic of modern materials science and nanotechnology that has not received proper attention, although it is critical, is understanding propagation of phonons across the interfaces between two crystalline materials. Vibrational spectroscopy in electron microscopy was first demonstrated only three years ago in a model system, and its practical application for studying phonon modes was demonstrated as recently as a few months ago. However, these demonstrations only occurred at low magnification, far from the atomic scale.

Jeong aims to be at the forefront of this very important scientific advancement by understanding local phonons at material interfaces. This understanding will also shed light on the less explored, but vitally important, topic of heat transport at the nano-, and even atomic, scale. The existing transmission electron microscopes (TEMs) in the Characterization Facility at the UMN do not meet the requirement for energy resolution in spectroscopy, even though the spatial resolution is good enough. To be at this exciting forefront of new instrumentational and scientific development, he will conduct experiments with phonon capability, in collaboration with the Rutgers group, on scientifically and technologically important materials and systems and bring this capability to the University of Minnesota through modifications of existing TEMs.

Funded by the National Science Foundation through the University of Minnesota MRSEC under Award Number DMR-1420013