Bandstructure and Fermi Surfaces of CeRh3B2

TL;DR

This paper calculates the electronic bandstructure and Fermi surfaces of ferromagnetic CeRh3B2, proposing a novel orbital- and spin-polarized ground state that explains experimental observations better than traditional models.

Contribution

It introduces a fully orbital- and spin-polarized ground state for CeRh3B2, challenging the conventional LS-coupled CEF ground state assumption.

Findings

The proposed ground state explains magnetic moments and dHvA frequencies.

Strong 4f-4f direct mixing stabilizes the unconventional ground state.

Calculated electronic structure matches experimental data.

Abstract

The electronic bandstructure and the Fermi surfaces of ferromagnetic CeRh3B2 are calculated by using FLAPW and LSDA+U method. As assuming several kinds of the ground state to describe the 4f electronic state, we propose a fully orbital- and spin-polarized state |lz=0, sx=1/2> as the ground state, instead of the conventional LS-coupled CEF ground state, generally expected in typical 4f compounds. This is supported by the fact that both the observed magnetic moment and the observed dHvA frequencies are well explained by the calculated electronic structure and the Fermi surfaces. The unconventional ground state is stabilized by the strong 4f-4f direct mixing between the neighbored Ce atoms along the extremely small distance along the c-axis in the hexagonal crystal cell.