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Testing density functional theory in a quantum Ising chain
发布时间:2021-10-11 11:54:08 332

演讲人Speaker:刘峥(清华大学)

题目Title:Testing density functional theory in a quantum Ising chain   

时间Date:2021年10月15日Time:10:00-11:00

地点Venue:G514会议室

(有学术小票)

 

内容摘要Abstract:By using the quantum Ising chain as a test bed and treating the spin polarization along the external transverse field as the “generalized density”, we examine the performance of different levels of density functional approximations parallel to those widely used for interacting electrons, such as local density approximation (LDA) and generalized gradient approximation (GGA). We show that by adding the lowest-order and nearest-neighbor density variation correction to the simple LDA, a semi-local energy functional in the spirit of GGA is almost exact over a wide range of inhomogeneous density distribution. In addition, the LDA and GGA error structures bear a high level of resemblance to the quantum phase diagram of the system. These results provide insights into the triumph and failure of these approximations in a general context.

 

个人简介(About the speaker):刘峥,2002年进入清华大学物理系,2006年本科毕业。2012年在清华大学高等研究院获物理学博士学位。毕业后在美国犹他大学做博士后研究。2015-2020年任清华大学高等研究院副研究员。2020年12月起任研究员。研究方向为凝聚态物理与材料科学的交叉领域,特别侧重从第一性原理计算出发准确识别量子材料的疑难性质,并结合实验数据及最新理论进展给出综合判断。同时致力于第一性原理计算应用边界的拓展,以及凝聚态物理前沿的核心问题与实际材料的对接。