Effects of chemical disorder in the itinerant antiferromagnet Ti$_{1-x}$V$_x$Au

TL;DR

This study investigates how chemical disorder from vanadium doping affects the magnetic properties of TiAu, revealing suppression of antiferromagnetism and signs of non-Fermi-liquid behavior away from the quantum critical point.

Contribution

It demonstrates the impact of V-induced disorder on magnetic order and non-Fermi-liquid signatures in TiAu, expanding understanding of disorder effects in itinerant antiferromagnets.

Findings

V doping suppresses antiferromagnetic order from 36 K to 10 K.

Signs of non-Fermi-liquid behavior observed in transport and heat capacity.

Chemical disorder influences magnetic and electronic properties away from QCP.

Abstract

The fragile nature of itinerant magnetism can be exploited using non-thermal parameters to study quantum criticality. The recently discovered quantum critical point (QCP) in the Sc-doped (hole-like doping) itinerant antiferromagnet TiAu (Ti$_{1-x}$Sc$_{x}$Au) raised questions about the effects of the crystal and electronic structures on the overall magnetic behavior. In this study, doping with V (electron-like doping) in Ti$_{1-x}$V$_{x}$Au introduces chemical disorder which suppresses antiferromagnetic order from $T_{\rm N} =$ 36~K for $x = 0$ down to 10 K for $x =$ 0.15, whereupon a solubility limit is reached. Signatures of non-Fermi-liquid behavior are observed in transport and specific heat measurements similar to Ti$_{1-x}$Sc$_{x}$Au, even though Ti$_{1-x}$V$_{x}$Au is far from a QCP for the accessible compositions $x \leq 0.15$.