报告题目:All defects are equal, but some are more equal than others: a disordered story
报告人:Prof. Matteo Baggioli(白玛窦 教授)
报告时间:2024年11月1日 上午9:30
报告地点:物理楼101
报告摘要:Topological defects play a fundamental role in modern physics from cosmic strings in the universe to vortices in superfluids. Topological defects, such as dislocations, are also essential to describe mechanical failure and plastic flow in crystalline materials. Amorphous solids (e.g., glasses), lacking an ordered lattice structure, are ubiquitous in nature and they also exhibit plastic behavior and soft spots -- regions more prone to local rearrangements. Nevertheless, a microscopic theory of these phenomena is still lacking because of the difficulty of defining defects in an already disordered environment.
In this talk, I will review recent developments claiming that topological defects can be still defined in disordered solids in the space of vibrational modes or in the dynamical displacement field. I will show how these defects can be correlated to soft spots and used to predict the plastic behavior in 2D and 3D glasses. Finally, by taking a step back and considering defective crystals, I will show how these newly proposed dynamical defects relate to well-established structural defects. I will comment on open questions and connections to other theories of defects in glasses.
报告人简介:Matteo Baggioli got his PhD in 2016 at Universidad Autonoma de Barcelona with a thesis on the application of gravitational and field theories to condensed matter systems. After two postdoctoral positions at the Crete center for theoretical physics and the institute of theoretical physics in Madrid, in 2020, he joined Shanghai Jiao Tong University as a tenure track associate professor. He is author of more than 100 articles published in international journals including, Review of Modern Physics, Nat.Commns, PRL, PNAS, Science Advances, ACS Nano and Physics Reports. In 2022, he was nominated among the Emerging Leaders by the Journal of Physics: Condensed matter. His research interests are highly interdisciplinary and span from liquid dynamics and vibrational properties of amorphous systems, to hydrodynamics and effective field theory, and finally to applications of the holographic duality to strongly correlated systems.