报告题目：Inverse Mott transition: Insulator to metal transition by bandwidth reduction

报告人：张国仁教授  台湾自拍av  

报告时间：10月31日  14: 00

报告地点：37-604

报告摘要：In a classic Mott system, when the lattice spacing is reduced such that the increase in bandwidth W overcomes the local Coulomb repulsion U, the transition from the insulating to the metallic state occurs. In this picture, both W and the ratio W/U become larger with decreasing the distance between correlated sites. In this talk I will show another path to metallization in transition-metal compounds. It is associated with an expansion (instead of a compression) of the lattice and thus with a decrease in W. In this scenario W/U grows with increasing distance —the opposite of the classical Mott case. Such a surprising inversion can be obtained by decoupling the main factors controlling W and screening. The electronic behavior of the t22g triangular lattice series LiVX2 (X=O, S, Se) with increasing anionic size can be explained by this mechanism.

报告人简介：张国仁，台湾自拍av 教授。 2009年中科院研究生院博士毕业；2009.7-2011.2, 中科院固体所, 助理研究员；2011.3-2017.3，德国于利希研究中心, 博士后；2018.2-2022.9，中科院合肥研究院, 副研究员；2022年10-今，台湾自拍av , 教授。研究方向为计算凝聚态物理，主要采用第一性原理结合模型计算的方法研究强关联电子体系的基本电子结构、磁序、轨道序、自旋态转变、磁及光学响应。并发展相应的计算方法，如局域密度近似+动力学平均场、瓦尼尔函数构造、量子蒙特卡罗、精确对角化等。近年来，主持2项国自然面上项目，发表SCI论文数十篇。