Connectivity between structure and dynamics in glass-forming liquids

报告题目:Connectivity between structure and dynamics in glass-forming liquids

报告人:梅 教授   北京大学量子材料科学中心




报告摘要:The structural description for the link between the fast vibrational dynamics and slow diffusive dynamics in glass-forming systems is one of the most challenging issues in physical science. Dynamic crossover is observed in many glass-forming liquids. Different scenarios, such phase transition, partial crystallization or glass transition, are proposed to explain such phenomenon. In this talk, I will discuss the structural origin and its correlation with dynamic transition in supercooled liquids. Particularly, in a model of metallic supercooled liquid, we find that local connectivity as an atomic-level structural order parameter tunes the short-time vibrational excitations of the icosahedrally coordinated particles and meanwhile modulates their long-time relaxation dynamics changing from stretched to compressed exponentials, denoting a dynamic transition from diffusive to hyperdiffusive motions. Our result indicates that long-time dynamics has a structural origin, thus suggesting a structural link the fast vibrational dynamics and the slow structural relaxation in glassy materials.

报告人简介:徐莉梅,北京大学教授,博士生导师。本科毕业于北京师范大学物理系,博士毕业于波士顿大学物理系。2008-2011年任日本东北大学助理教授;2011年至今,先后任北京大学物理学院副教授、教授。主要从事凝聚态物理、表面物理、统计物理等方面的研究,主要研究方向包括临界现象及相变、界面分子的谱学研究、液体的结构与动力学等。在相关领域的主要物理类期刊杂志发表多篇学术论文,包括NatureNature PhysicsProc. Natl. Acad. Sci., Phys. Rev. Lett.Nature Comm等。主持和参与多项国家自然科学基金委面上项目、重大项目、及科技部重大研发计划。2011年入选国家千人计划-青年千人;2015年获批国家自然科学基金委杰出青年基金;现任中国物理学会理事会理事、担任《中国物理》杂志编委等。