CeNiAsO: an antiferromagnetic dense Kondo lattice

TL;DR

This study investigates CeNiAsO, revealing it as an antiferromagnetic dense Kondo lattice with complex magnetic transitions and strong electron correlations, but no superconductivity down to very low temperatures.

Contribution

It provides detailed experimental characterization of CeNiAsO's magnetic and electronic properties, highlighting the role of 3d-4f interlayer Kondo interactions in Ni-based Ce pnictides.

Findings

CeNiAsO is an antiferromagnetic dense Kondo lattice.

Two successive antiferromagnetic transitions at 9.3 K and 7.3 K.

No superconductivity observed down to 30 mK.

Abstract

A cerium containing pnictide, CeNiAsO, crystallized in the ZrCuSiAs type structure, has been investigated by measuring transport and magnetic properties, as well as specific heat. We found that CeNiAsO is an antiferromagnetic dense Kondo lattice metallic compound with Kondo scale $T_K \sim$ 15 K and shows an enhanced Sommerfeld coefficient of $\gamma_0 \sim$ 203 mJ/mol$\cdot$K$^{2}$. While no superconductivity can been observed down to 30 mK, Ce ions exhibit two successive antiferromagnetic (AFM) transitions. We propose that the magnetic moment of Ce ion could align in the G type AFM order below the first transition at $T_{N1}$=9.3 K, and it might be modified into the C type AFM order below a lower transition at $T_{N2}$=7.3 K. Our results indicate that the 3$d-4f$ interlayer Kondo interactions play an important role in Ni-based Ce-containing pnictide.