Hund's metallicity enhanced by a van Hove singularity in cubic perovskite systems
Abstract
A van Hove singularity (VHS) often significantly amplifies the electronic instability of a crystalline solid, including correlation-induced phenomena such as Hund's metallicity. We perform a systematic study on the interplay between Hund's coupling and electronic structures with a VHS focusing on Hund's metallicity. We construct a simplified tight-binding model targeting cubic perovskite materials and test the effects of the VHS utilizing dynamical mean-field theory with an exact diagonalization solver. The quasiparticle weight and the low-frequency power exponent of the self-energy provide a quantitative estimation of metallicity over the phase diagram. We find the VHS to substantially enhance Hund's metallicity. The results here suggest a range of parameters through which a VHS can bring great synergy with Hund's coupling.
- Publication:
-
Physical Review B
- Pub Date:
- October 2021
- DOI:
- 10.1103/PhysRevB.104.165138
- arXiv:
- arXiv:2107.05906
- Bibcode:
- 2021PhRvB.104p5138L
- Keywords:
-
- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- 7 pages, 6 figures