题目：Aperiodic quantum oscillations in the two-dimensional electron gas at the LaAlO₃/SrTiO₃ interface

报告人：Dr. Walter Escoffier

               法国国家科学研究中心、图卢兹强磁场实验室

时间：2019年4月24日（星期三）下午15:30

地点：国家脉冲强磁场科学中心B206

报告摘要：

We investigate the transport properties of a high-mobility quasi-two-dimensional electron gas at the interface between two insulators LaAlO₃and SrTiO₃. Since its first discovery in 2004, the electronic band structure derived from magnetotransport studies in different experimental conditions of temperature and magnetic field provided equivocal conclusions. Recently, the use of high magnetic field clearly revealed non 1/B-periodic magneto-resistance oscillations, as evidenced by a highly non-linear Landau plot (Landau level index versus 1/B). Among various scenarios, the Roth-Gao-Niu model provides a natural explanation for this effect, in relation with the magnetic response functions of the system. The experimental magneto-transport results are discussed jointly with dedicated theoretical DFT band-structure calculations, as well as with structural analysis of the interface using high-resolution scanning transmission electron microscopy.

报告人简介：

Dr. Walter Escoffier obtained his PhD in Physics in 2004 from the University Joseph Fourier in Grenoble (France), before working for two years as a post-doc at the Department of Physics and Astronomy of the University of Manchester (U.K.). In 2006, he became associate professor at the “Laboratoire National des Champs Magnétiques Intenses” (LNCMI) of Toulouse (France) and obtained the "Habilitation à Diriger des Recherches" in 2012. Dr. Walter Escoffier leads the research group “Nano-objects and semi-conducting nano-structures” which is specialized in the investigation of electronic properties of low dimensional objects such as carbon nanotubes, semiconducting or metallic nanowires, or two-dimensional electron gas such as graphene or transition metal dichalcogenides. Recently, his research team focuses particularly on the electronic properties of two-dimensional electron gas arising at the interface between complex oxides.