From magnetic to Fermi Liquid behavior in CeCo{1-x}Fe{x}Si alloys

TL;DR

This study investigates how substituting Fe for Co in CeCoSi alloys affects their magnetic and electronic properties, revealing a transition from magnetic order to Fermi liquid behavior with increasing Fe content.

Contribution

It provides a detailed phase diagram of CeCo{1-x}Fe{x}Si alloys, identifying regions of magnetic order, short-range correlations, and Fermi liquid behavior based on structural, magnetic, and thermal measurements.

Findings

Magnetic order diminishes with increasing Fe content.

A broad magnetic anomaly appears in specific heat at intermediate compositions.

Transition from non-Fermi-liquid to Fermi-liquid behavior occurs as Fe concentration increases.

Abstract

Structural, magnetic and thermal measurements performed on CeCo{1-x}Fe{x}Si alloys are reported. Three regions can be recognized: i) Co-rich (x < 0.20) with a decreasing long range antiferromagnetic order which vanishes at finite temperature, ii) an intermediate region (0.20 < x < 0.30) showing a broad magnetic anomaly (C_A) in specific heat and iii) the non-magnetic region progressively changing from a non-Fermi-liquid type behavior towards a Fermi liquid one as Fe concentration increases. The C_A anomaly emerges as an incipient contribution above T_N already at x = 0.10, which indicates that this contribution is related to short range correlations likely of quasi-two dimensional type. Both, T_N transition and C_A anomaly are practically not affected by applied magnetic field up to B ~ 10 Tesla.