报告题目：Using Advanced High-Pressure Techniques to Study Material Properties in Extreme Environments
报 告 人：Jung-Fu “Afu” Lin (林俊孚), Department of Geological Sciences, Jackson School of Geosciences
In this talk, I will present my recent research results and lab/life building experiences from the prospective of a new faculty at UT Austin to illustrate how I build my career and research program so far successfully at Texas. My recent research interest focuses on understanding material properties in extreme environments using advanced synchrotron X-ray and laser spectroscopic techniques coupled with a high-pressure diamond anvil cell. Specifically, I have focused on understanding transition metal iron that belongs to the 3d transition metal group and forms a series of compounds with a uniquely wide range of electronic, magnetic, elastic, and thermodynamic properties. Iron is the most abundant transition metal in the universe and in the Earth’s interior, and thus has a wide range of material science and geoscience applications as well. As a result of the partially-filled 3d electronic orbital, iron exists in a variety of electronic spin and valence states including metallic, ferrous, and ferric ions as well as high-spin and low-spin states. Here I will present recent results on pure iron, iron alloys, iron pnictides, ferropericlase, and magnetite to illustrate the interplays between electronic, magnetic, and structural properties of iron compounds in extreme high-pressure and high/low-temperature environments. The advent of the synchrotron-based inelastic X-ray scattering spectroscopies offers a plethora of research opportunities to investigate material properties of these compounds at extreme P-T environments. These studies unleash new insights into phonon dispersion curves, phonon density of states, electronic structures (e.g., spin and valence states), magnetism, elasticity, and bonding characters of the iron compounds. I will also present our recent research results and progresses using Brillouin Light Scattering spectroscopy and time-resolved laser spectroscopy in a high-pressure diamond anvil cell.