报告题目：First-principles studies of complex oxides and their interfaces

报 告 人：Chris G. Van de Walle,Materials Department, University of California, Santa Barbara, California, USA

报告时间：2015年6月11日16：00

报告地点：理科楼郑裕彤大讲堂

报告摘要：The formation of a two-dimensional electron gas (2DEG) at the interface between two complex oxides has sparked huge interest in oxide electronics. In spite of more than a decade of research, many fundamental aspects, including the mechanisms that determine the density of this 2DEG, are still imperfectly understood. We have used hybrid density functional theory to elucidate fundamental materials properties and calculate key parameters for heterojunctions. I will discuss Mott-Hubbard gaps of rare-earth titanates, the formation and excitation of small hole polarons, and how confinement effects in thin SrTiO3 layers can trigger a metal-insulator transition.

Work performed in collaboration with L. Bjaalie, L. Gordon, B. Himmetoglu, A. Janotti, A. Verma, S. Raghavan, D. Jena, D. G. Ouellette, P. Moetakef, T. A. Cain, S. J. Allen, and S. Stemmer, and supported by NSF, SRC/DARPA, ARO, and ONR.