A Model for Correlated Metamagnets: Application to UPt$_3$ and CeRu$_2$Si$_2$

TL;DR

This paper presents a self-consistent model of three S=1 pseudo-spins with anisotropic interactions, successfully reproducing the thermodynamic properties of UPt$_3$ and CeRu$_2$Si$_2$, and offers predictions for future experiments.

Contribution

It introduces a minimal, self-consistent model for correlated metamagnets that accurately matches experimental data and provides testable predictions.

Findings

Reproduces thermodynamic responses of UPt$_3$ and CeRu$_2$Si$_2$

Predicts specific experimental signatures for further validation

Highlights the role of anisotropic mean fields and level broadening

Abstract

In a model system with three S=1 pseudo-spins situated in an anisotropic mean field we compute the thermodynamic response in a self consistent manner. An adhoc uniform broadening of all energy levels of the (localized) spins due to their interaction with conduction electrons is introduced. The results with a minimal set of parameters reproduce with remarkable fidelity the properties of the strongly correlated metamagnets UPt$_3$ and CeRu$_2$Si$_2$. Several key predictions are made for further experimental confirmation.