Phase diagram of CeSb$_2$ from magnetostriction and magnetization measurements: Evidence for ferrimagnetic and antiferromagnetic states

TL;DR

This study maps the complex magnetic phase diagram of CeSb$_2$ using magnetostriction and magnetization measurements, revealing a ferrimagnetic ground state and electronic structure reconstruction in this rare earth magnetic material.

Contribution

It provides detailed experimental insights into the magnetic phases and electronic structure of CeSb$_2$, highlighting its ferrimagnetic ground state and phase transitions.

Findings

Low temperature ground state is ferrimagnetic.

Electronic structure reconstructs near the Fermi energy in magnetic phases.

Magnetostriction and magnetization measurements map the phase diagram.

Abstract

Cerium diantimonide (CeSb$_2$) is one of a family of rare earth based magnetic materials that exhibit metamagnetism, enabling control of the magnetic ground state through an applied magnetic field. At low temperatures, CeSb$_2$ hosts a rich phase diagram with multiple magnetically ordered phases for many of which the order parameter is only poorly understood. In this paper, we report a study of its metamagnetic properties by Scanning Tunneling Microscopy (STM) and magnetization measurements. We use STM measurements to characterize the sample magnetostriction with sub-picometer resolution from magnetic field and temperature sweeps. This allows us to directly assess the bulk phase diagram as a function of field and temperature and relate spectroscopic features from tunneling spectroscopy to bulk phases. Our magnetostriction and magnetisation measurements indicate that the low temperature ground state at zero field is ferrimagnetic. Quasiparticle interference mapping shows evidence for a reconstruction of the electronic structure close to the Fermi energy upon entering the magnetically ordered phase.