摘要

Establishing a complete picture of phonon dispersions and mean-free-paths is important to understand the microscopic characterization of phonon transport, and design an efficient thermoelectric compound. As a very useful tool, the neutron scattering technique can not only map phonon dispersions, but also the lifetimes across the entire Brillouin zone. These measurements provide key insights about phonon scattering mechanisms, such as phonon anharmonicity, and scattering by point defects or nanostructures. Furthermore, the first-principles simulations of atomic dynamics are performed. We present the results from the studies of several important thermoelectric materials, PbTe, SnTe, and AgSbTe2, and illustrate how this integrated approach can be used to reach a new level of understanding of the thermal conductivity.

报告人简介

马杰，2003年本科毕业于中国科学技术大学材料科学与工程系，2010年于美国衣阿华州立大学物理系获博士学位。2010-2014在美国橡树岭国家实验室的中子中心任博士后研究员；2015年开始同时在美国橡树岭国家实验室和田纳西大学任博士后研究员。

主要运用中子散射技术对热电材料和磁性材料的晶体结构、声子谱和磁子谱进行研究，探讨体系中相关的量子效应等物理机制。同时, 也熟练掌握合金、氧化物等材料的常用物理制备方法（例如布里奇曼法和光学浮区法等）以及输运特性的表征技术，并且对中子仪器的设计，维护和操作都有丰富的经验。发表文章24篇，包括Nature Mater.,  Nature Nano., Phys. Rev. Lett. 等。