报告人：强游教授

          Physics Department, University of Idaho, Moscow ID 83844-0903

报告时间: 2019年7月9日上午10:00

报告地点：知新楼C1111

邀请人：田玉峰 教授

报告摘要：

NON-VOLATILE MEMORIEs (NVMs) are required in a variety of nuclear and space applications for data or code storage. In the past years, a large amount of work has been devoted to study radiation effects in a wide cross section of commercial NVMs, such as floating-gate, GMR, TMR and ferroelectrics. Designing a nanomaterial from the atomic level to achieve a radiation tolerance in extreme conditions is a grand challenge in logic and memory research. Our investigation is focusing on fundamental understandings of the interactions between point defects and grain boundaries. It was found that important consideration of GBs that quantify the efficiency of sinks to annihilate point defects. This surprising finding provides a novel opportunity to enhance the radiation resistance of nanomaterials through GB engineering. Our atomistic simulation has demonstrated that the GBs have a “loading-unloading” effect that happens from picosecond. Such GBs can serve as effective sinks for radiation-induced defects such as interstitials and vacancies. Upon irradiation, interstitials are loaded into the boundary, which then acts as a source, emitting interstitials to annihilate vacancies in the materials. Nanomaterials provide a path to radiation tolerance because GBs that attract, absorb and annihilate point defects.

报告人简介：

Dr. Qiang is Professor of Physics and the core-faculty of Nuclear Engineering Program at the University of Idaho and Idaho National Laboratory, USA. He is the director of Nanophysics and Nanomaterials Research Laboratory. He is also the President and Fellow of Idaho Academy of Science and Engineering. He received his MS degree 1985 at the Harbin Institute of Technology and Chinese Academy of Space Technology, and Ph.D. degree in 1997 at the University of Freiburg, Germany. Dr. Qiang’s research focuses on nanomagnetism and magnetic nanomaterials, including synthesis of monodispersive nanoclusters and nanocluster-assembled composites; characterization of magnetic and optical properties as well as spintronics by conductivity, optics, susceptibility and theoretical investigation on magnetic interactions. Recently investigations are focusing on radiation effects on nanomaterials for nuclear energy application.