美国路易斯安那州立大学Jiandi Zhangj教授和
美国罗格斯大学Jak Chakhalian教授学术报告
报告时间：2017年6月8日上午
报告地点：格致楼5004报告厅
报告一：Interface-driven quantum magnetic phenomena in oxide heterostructures
报告时间：6月8日上午9：30
报告人：Jiandi Zhang
报告摘要：I will introduce our ability in growing high quality thin films with atomically sharp interfaces, as well as powerful tools to characterize their properties down to atomic resolution, which allow us to explore unconventional interfaces and search for novel quantum functionality.I will discuss recent studies of oxide heterostructures, such as La2/3Sr1/3MnO3/SrTiO3(001). We reveal that broken symmetry results in dramatic modification of structure/chemistry at the interface. As a result, antiferromagnetic coupling emerges at the interface region which leads to spontaneous magnetic reversal and inverted hysteresis persisting well above room temperature. We further show that it is possible to engineer a self-assembled interface in a single thin film material by special processing techniques. Our results indicate that interface-driven interactions can go beyond the proximity of the interface and govern the properties of the entire thin film which presents a new pathway for designing functional oxide heterostructures.
个人简介：Prof. Jiandi Zhang received B.S. and M.S. degrees in physics from the Nanjing University of Science and Technology in 1982 and the Chinese Academy of Science (CAS) in 1986, respectively. Then he was on the faculty of Shanghai Jiao Tong University between 1986 and 1989. He received his Ph.D. degree in physics from Syracuse University in 1994, spent about one year at University of Nebraska-Lincoln and 3 years as a postdoc fellow at Oak Ridge National laboratory/the University of Tennessee prior to joining the Florida International University as a faculty member in 1998. Starting from 2009, he became a full professor in physics at Louisiana State University. He is also a visiting professor at CAS since 2007. He has published more than 110 peer-reviewed research articles. He is a fellow of American Physical Society.
报告二：How to design artificial quantum materials
报告时间：6月8日上午10：30
报 告 人：Jak Chakhalian
报告摘要：Complex oxides with correlated electrons are a class of materials characterized by multiple competing and nearly degenerate ground states due to interactions that create a subtle balance to define the lowest energy state. This leads to a wide diversity of intriguing properties ranging from high Tc superconductivity to exotic magnetism and orbital phenomena. By utilizing the bulk properties of these materials as a starting point, interfaces between different classes of complex oxides offer a unique opportunity to break the fundamental symmetries of the bulk and alter the local environment. Utilizing our recent advances in oxide growth, we can now combine layers of materials with distinct order parameters to design novel artificial quantum materials with atomic layer precision. The broken lattice symmetry, strain, and altered chemical and electronic environments at the interfaces then provide a unique platform to manipulate this subtle balance and enable novel quantum states not attainable in the bulk. Understanding of these phases however requires detailed microscopic studies of the heterostructure properties. In this talk I will present our recent results on designer magnetic 2DEG and artificial polar metal in tri-color titanates illustrate uncovered principles of rational materials design and control of interactions.
个人简介：
2016–present Claud Lovelace Chair and Professor of Physics, Rutgers.
2012–2016 Charles and Clydene Scharlau Endowed Chair and Professor of Physics, University of Arkansas.
2010–2012 Charles and Clydene Scharlau Endowed Chair and Associate Professor of Physics, University of Arkansas.
2006–2010 Assistant Professor, University of Arkansas.
