English

Hund electronic correlation in La$_3$Ni$_2$O$_7$ under high pressure

Strongly Correlated Electrons 2024-05-17 v1 Materials Science Superconductivity

Abstract

By means of density functional theory plus dynamical mean-field theory (DFT+DMFT), we investigate the correlated electronic structures of La3_3Ni2_2O7_7 under high pressure. Our calculations show that La3_3Ni2_2O7_7 is a multi-orbital Hund metal. Both the 3dz2d_{z^2} and 3dx2y2d_{x^2 - y^2} orbitals of Ni are close to be half filled and contribute the bands across the Fermi level. Band renormalization and orbital selective electronic correlation are observed. Through imaginary-time correlation functions, the discovery of high-spin configuration, spin-frozen phase, and spin-orbital separation shows that the system is in a frozen moment phase at high temperatures above 290 K and is a Fermi liquid at low temperatures, which is further comfirmed by the calculated spin, orbital, and charge susceptibilities under high temperatures. Our study uncovers Hundness in La3_3Ni2_2O7_7 under high pressure.

Keywords

Cite

@article{arxiv.2311.10066,
  title  = {Hund electronic correlation in La$_3$Ni$_2$O$_7$ under high pressure},
  author = {Zhenfeng Ouyang and Jia-Ming Wang and Jing-Xuan Wang and Rong-Qiang He and Li Huang and Zhong-Yi Lu},
  journal= {arXiv preprint arXiv:2311.10066},
  year   = {2024}
}

Comments

6 pages, 5 figures, 2 tables