English

Lifshitz Transition and Nontrivial H-Doping Effect in Cr-based Superconductor KCr$_3$As$_3$H$_x$

Superconductivity 2019-10-16 v2 Materials Science Strongly Correlated Electrons

Abstract

We report the first-principles study on the H-intercalated Cr-based superconductor KCr3_3As3_3Hx_x. Our results show a paramagnetic ground state for KCr3_3As3_3H. The electronic structure consists of two quasi-one-dimensional (Q1D) Fermi-surfaces and one 3D Fermi-surface which are mainly contributed by Cr-dz2_{z^2}, dx2y2_{x^2-y^2} and dxy_{xy} orbitals. The bare electron susceptibility shows a Γ\Gamma-centered imaginary peak, indicating possible ferromagnetic spin fluctuations. Upon moderate hole doping, the system undergoes a Lifshitz transition, which may enhance the Q1D feature of the system. The Bader charge analysis and electron localization functions reveal a strong bonding nature of hydrogen in KCr3_3As3_3H, which results in a nontrivial electron doping in KCr3_3As3_3H.

Keywords

Cite

@article{arxiv.1908.05393,
  title  = {Lifshitz Transition and Nontrivial H-Doping Effect in Cr-based Superconductor KCr$_3$As$_3$H$_x$},
  author = {Si-Qi Wu and Chao Cao and Guang-Han Cao},
  journal= {arXiv preprint arXiv:1908.05393},
  year   = {2019}
}