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arXiv · 1806.04729

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

C. -L. Huang·J. M. Santiago·E. Svanidze·T. Besara·T. Siegrist·E. Morosan
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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 $x \leq 0.15$.

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C. -L. Huang, J. M. Santiago, E. Svanidze, T. Besara, T. Siegrist, E. Morosan. 2018-06-12. Effects of chemical disorder in the itinerant antiferromagnet Ti$_{1-x}$V$_x$Au. https://doi.org/10.1088/1361-648x/aad832

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