English

Spin-orbit coupling induced orbital entanglement in a three-band Hubbard model

Strongly Correlated Electrons 2024-09-30 v2

Abstract

The effect of the spin-orbit coupling on the ground state properties of the square-lattice three-band Hubbard model with a single electron per site is studied by a generalized Hartree-Fock approximation. We calculate the full phase diagram and show that there appear additional orbital-entangled phases brought about by competition of various exchange channels or by the spin-orbit coupling in addition to conventional states stabilized by the Kugel-Khomskii mechanism. One of these phases previously proposed to explain magnetic properties of Sr2_2VO4_4 is characterized by vanishing dipolar magnetic moments and antiferro-octupolar ordering. We calculated microscopic parameters for this material and demonstrate that it is located near a phase boundary of two orbital-entangled and two conventional antiferromagnetic ferro-orbital states.

Keywords

Cite

@article{arxiv.2406.07386,
  title  = {Spin-orbit coupling induced orbital entanglement in a three-band Hubbard model},
  author = {Petr A. Igoshev and Danil E. Chizhov and Valentin Yu. Irkhin and Sergey V. Streltsov},
  journal= {arXiv preprint arXiv:2406.07386},
  year   = {2024}
}