报告人：马杰 教授 (上海交通大学)

时 间：2024年11月25日(周一)上午10：00-12：00

地 点：良乡校区，理学楼B203会议室

摘要：

As a typical quantum energy material, thermoelectric compounds have attracted a lot of attention both in scientific research and industrial design in recent years. Although lattice thermal conductivity is an important parameter to determine the figure-of-merit of thermoelectricity, the research on the phonons is still limited. If a complete phonon scattering spectra and related lattice vibration image could be established in those kinds of narrow bandgap semiconductor system, the phonon transport characteristics can be decided from a kinetic point of view and regulated accordingly at the microscopic level, even a highly efficient thermoelectric or low thermal conductivity material system can be designed to a great extent. Neutron scattering is a typical technique for studying structure and dynamics, which can not only accurately obtain the energy dispersion relationship, but also map the phonon lifetime of the entire Brillouin region. These measurements provide key information for studying phonon scattering mechanisms, such as phonon dissonance, point defects, nanostructures, and "liquid-like" behavior. Starting from the cubic structure of VI-IV compounds, we will study the related lattice thermal conductivity, combined with molecular dynamics simulation, to explore the mechanism of suppressing the related acoustic phonon and optical phonon, and then use a variety of coordinated methods to study the thermal conductivity from the perspective of phonon control.

Reference:

[1] J. Wu, Y. Lin, M. Shu et. al., Nat. Comm. 15, 6248 (2024)

[2] J. Zhu, Q. Ren, C. Chen et. al., Nat. Comm. 15, 2618 (2024)

[3] Q. Ren, M. K. Gupta, M. Jin et. al., Nat. Mater. 22, 999 (2023)

[4] S. Han, S. Dai, J. Ma et. al., Nat. Phys. 19, 1649 (2023)

[5] Q. Ren, C. Fu, Q. Qiu et. al., Nat. Comm. 11, 3142 (2020)

简历：

马杰，上海交通大学物理与天文学院教授。本科毕业于中国科学技术大学,博士毕业于美国衣阿华州立大学,之后在美国橡树岭国家实验室/田纳西大学开展博士后工作。已在Science, Nat. Mater., Nat. Phys., Phys. Rev. Lett.等杂志上发表论文120多篇，引用8100余次。中国晶体学会粉末衍射专业委员会委员, Chinese Physics Letters、Chinese Physics B、《物理学报》和《物理》四刊青年编委，长期担任Nat. Phys.、Nat. Mater.、Phys. Rev. Lett.等杂志审稿人。主要从事凝聚态物理实验研究方面的工作，在生长样品的同时，运用中子散射、缪子自旋弛豫/旋转及同步辐射X光技术对强关联材料的晶体/磁结构及相关动力学谱进行研究，探讨这类材料在极端条件下的复杂相互作用及其导致的诸如电荷有序、轨道晶格耦合、电声耦合等新奇量子效应，并对这些奇异物性开展调控。

联系方式：xiangli@bit.edu.cn

邀 请 人：李翔 教授

网 址：/

承办单位：7003全讯入口、先进光电量子结构设计与测量教育部重点实验室