报告题目：Emergent topological phenomena in quench dynamics
报告人：易为
中国科学技术大学教授、博士生导师。1977年生于上海，2000年于中国科学技术大学应用物理系获学士学位，2007年获美国密歇根大学(University of Michigan)物理学博士学位，2007年至2010年先后在密歇根大学和奥地利因斯布鲁克大学理论物理所从事博士后研究。2010年5月始至今在中国科学技术大学光学与光学工程系工作。主要的研究方向包括超冷原子、量子模拟和多体强关联系统。
With rapid progress in the discovery and understanding of topological phases in solid-state materials, a challenging quest lies in extending the study of conventional topological matter to novel regimes. A prominent example is the investigation of emergent topological properties in out-of-equilibrium dynamics. Here We show that dynamical quantum phase transitions (DQPTs) in the quench dynamics of two-dimensional topological systems can be characterized by a dynamical topological invariant defined along a one-dimensional closed contour in momentum space. We demonstrate that when the contour crosses topologically protected fixed points in the quench dynamics, an intimate connection can be established between the dynamical topological order parameter in two dimensions and those in one dimension. We further define a reduced rate function of the Loschmidt echo on the contour, which features non-analyticities at critical times and is sufficient to characterize DQPTs in two dimensions. We illustrate our results using the Haldane honeycomb model and the quantum anomalous Hall model as concrete examples, both of which have been experimentally realized using cold atoms.
时间：2018年5月26 上午9:30
报告地点：理论物理研究所学术报告厅