# Two-orbital model for CeB$_6$

## TL;DR

This paper develops a two-orbital tight-binding model for CeB$_6$ that reproduces key Fermi surface features observed in ARPES experiments and explores multipolar susceptibilities related to magnetic correlations.

## Contribution

It introduces a novel two-orbital model based on the $ ext{Gamma}_8$ quartet that accurately captures CeB$_6$'s Fermiology and analyzes its multipolar susceptibilities under Coulomb interactions.

## Key findings

- Model reproduces ellipsoid-like Fermi surfaces aligned along $ ext{Gamma}$-X.
- Identifies the susceptibility with the strongest divergence indicating potential magnetic ordering.
- Suggests relevance of ferromagnetic correlations in CeB$_6$ phases.

## Abstract

We describe a two-orbital tight-binding model with bases belonging to the $\Gamma_8$ quartet. The model captures several characteristics of the Fermiology unravelled by the recent angle-resolved photoemission spectroscopic (ARPES) measurements on cerium hexaboride CeB$_6$ samples cleaved along different high-symmetry crystallographic directions, which includes the ellipsoid-like Fermi surfaces (FSs) with major axes directed along $\Gamma$-X. We calculate various multipolar susceptibilities within the model and identify the susceptibility that shows the strongest divergence in the presence of standard onsite Coulomb interactions and discuss it's possible implication and relevance with regard to the signature of strong ferromagnetic correlations existent in various phases as shown by the recent experiments.