Hosung is currently working on the microscopic theory of nano-scale oxide heterostructures, mainly employing first-principles density functional calculations. This revolutionary class of oxide systems has been recently realized owing to advanced oxide thin film deposition techniques such as molecular beam epitaxy. These materials systems are very interesting and hold tremendous promise because one can now create a lot of exotic quantum phases and novel functional properties, which were not present in the nature before and may lead to high-impact technological electronic devices in the future. So he and his peers try to learn how to understand them, control them and design new materials systems.
However, these are very challenging because he and his peers should working on interfaces between very dissimilar oxide materials at the atomic length scale! In their research group led by Professor Alexander Demkov in the physics department, Hosung and his peers perform truly interdisciplinary research work combining theory and experiment, which are being performed by researchers from physics and engineering departments. In the Materials Physics Lab, they synthesize new materials everyday using molecular beam epitaxy and atomic layer deposition and probe their electronic properties using various spectroscopic techniques including angle-resolved photoemission spectroscopy.
In the past few years, he and his peers have observed a variety of interesting and surprising physical properties of their oxide systems that they have created in their lab. It includes strain controlled spin state transition in LaCoO3, surface core level shift in a Sr Zintl template driven by final state effects, etc. As a theorist, he has been mainly working to provide theoretical models to explain the experimental puzzles observed in the Materials Physics Lab and trying to help people design new experiments and new materials. All of this work has been performed in close collaboration and interaction with experiments. He is proud and excited about the research environment and opportunity that he has in the Demkov group because there are few places in the world which are equipped with these capabilities.
He hopes that his research will make a significant contribution not only to the discovery of new physics and the fundamental understanding of oxide heterostructures, but also to technological advances for our society.
B.S. Seoul National University
M.S. Northwestern University
Photo by Roxanne Rathge © UT Austin