English

Weyl nodal point-line Fermion in ferromagnetic Eu$_5$Bi$_3$

Materials Science 2019-09-13 v1

Abstract

Based on abab initioinitio calculations and low-energy effective kpk{\cdot}p model, we propose a type of Weyl nodal point-line fermion, composed of 0D Weyl points and 1D Weyl nodal line, in ferromagnetic material Eu5_5Bi3_3. In the absence of spin-orbital coupling (SOC), the spin-up bands host a pair of triply degenerate points together with a unique bird-cage like node structure. In the presence of SOC with (001) magnetization, each triplet point splits into a double Weyl point and a single Weyl point accompanied by two nodal rings, forming two sets of Weyl nodal point-line fermions near the Fermi level. The novel properties of Weyl nodal point-line fermion are explored by revealing the unusual Berry curvature field and demonstrating the pinned chiral surface states with exotic Fermi arcs at different planes. Moreover, a large anomalous Hall conductivity of -260 (\hbar/ee)(Ω\Omegacm)1^{-1} parallel to [001] direction is predicted. Our work offers a new perspective for exploring novel topological semimetal states with diverse band-crossing dimensions, and provides an ideal material candidate for future experimental realiztion.

Keywords

Cite

@article{arxiv.1902.00894,
  title  = {Weyl nodal point-line Fermion in ferromagnetic Eu$_5$Bi$_3$},
  author = {Hongbo Wu and Da-Shuai Ma and Botao Fu and Wei Guo and Yugui Yao},
  journal= {arXiv preprint arXiv:1902.00894},
  year   = {2019}
}

Comments

19 pages, 4 figures