Variational Monte Carlo study for the insulating mechanism of Sr2IrO4: from the viewpoint of energy gain

24th IUPAP Conference on Computational Physics

物理学;计算机科学

Watanabe, Hiroshi^1,2,3 ; Shirakawa, Tomonori^1,2,3 ; Yunoki, Seiji^1,2,3

Computational Condensed Matter Physics Laboratory, RIKEN ASI, Saitama 351-0198, Japan^1

CREST, Japan Science and Technology Agency (JST), Saitama 332-0012, Japan^2

Computational Materials Science Research Team, RIKEN AICS, Kobe, Hyogo 650-0047, Japan^3

关键词: 5d electron systems;    Antiferromagnetic state;    Different mechanisms;    Ground state phase diagram;    Ground state properties;    Interaction energies;    Variational Monte Carlo;    Variational Monte Carlo method;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/454/1/012047/pdf
DOI  :  10.1088/1742-6596/454/1/012047

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

To examine the insulating mechanism of a novel 5d-electron system Sr2IrO4, we study the ground state properties of a three-orbital Hubbard model using a variational Monte Carlo method. We find that the insulating state in the ground state phase diagram shows crossover behavior from a weakly-correlated to a strongly-correlated antiferromagnetic state. This crossover is characterized by the different mechanisms of the insulating state, i.e., changing from an interaction-energy driven insulator to a band-energy driven insulator with increasing the interaction. We discuss that Sr2IrO4is located around this crossover region and displays an anomalous behavior.