Tuning the hybridization and magnetic ground state of electron and hole doped CeOs$_2$Al$_{10}$: an x-ray spectroscopy study

TL;DR

This study uses soft x-ray absorption spectroscopy to explore how electron and hole doping affect the magnetic and electronic properties of CeOs$_2$Al$_{10}$, revealing changes in hybridization and magnetic ground state.

Contribution

It provides new insights into how doping influences hybridization and magnetic order in CeOs$_2$Al$_{10}$ using advanced x-ray spectroscopy techniques.

Findings

Doping alters the hybridization between conduction and 4f electrons.

The high Neel temperature is maintained despite doping.

Strong Kondo screening is observed along the a crystallographic direction.

Abstract

Here we present linear and circular polarized soft x-ray absorption spectroscopy (XAS) data at the Ce $M_{4,5}$ edges of the electron (Ir) and hole-doped (Re) Kondo semiconductor CeOs$_2$Al$_{10}$. Both substitutions have a strong impact on the unusual high N$\acute{e}$el temperature, $T_N$=28.5\,K, and also the direction of the ordered moment in case of Ir. The substitution dependence of the linear dichroism is weak thus validating the crystal-field description of CeOs$_2$Al$_{10}$ being representative for the Re and Ir substituted compounds. The impact of electron- and hole-doping on the hybridization between conduction and 4$f$ electrons is related to the amount of $f^0$ in the ground state and reduction of x-ray magnetic circular dichroism. A relationship of $cf$-hybridization strength and enhanced $T_N$ is discussed. The direction and doping dependence of the circular dichroism is in agreement with strong Kondo screening along the crystallographic $a$ direction.