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arXiv · 2212.00579

Weyl Metal Phase in Delafossite Oxide PtNiO$_2$

Gang Bahadur Acharya·Mohan Bikram Neupane·Rojila Ghimire·Madhav Prasad Ghimire
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Abstract

On the basis of density functional theory calculations we predict Weyl points in rhombohedral structure of PtNiO$_2$ having symmorphic symmetry. From the formation energy and phonon calculations, PtNiO$_2$ is found to be structurally stable. The magnetic ground state is ferromagnetic with an effective magnetic moment of 1.01 $\mu_B$ per unit cell. The electronic structure shows major contributions from Pt-$5d$, Ni-$3d$ and O-$2p$ orbitals with band crossing close to the Fermi level. The orbital contribution around 8 eV above the Fermi level are from the Pt-$s,p$ orbitals forming a kagome like electronic structure confirmed by surface Fermi surface spectral function. We found 20 pairs of confirmed Weyl nodes along the magnetic easy axis [100]. These results are expected to provide a useful and exciting platform for exploring and understanding the magnetic Weyl physics in delafossites.

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Gang Bahadur Acharya, Mohan Bikram Neupane, Rojila Ghimire, Madhav Prasad Ghimire. 2022-12-01. Weyl Metal Phase in Delafossite Oxide PtNiO$_2$. https://arxiv.org/abs/2212.00579

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