We present an experimental realization of a quantum critical point in an itinerant antiferromagnet composed of nonmagnetic constituents, TiAu. By partially substituting Ti with Sc in ${\mathrm{Ti}}_{1-x}{\mathrm{Sc}}_x\mathrm{Au}$, a doping amount of $x_c=0.13\pm 0.01$ induces a quantum critical point with minimal disorder effects. The accompanying non-Fermi liquid behavior is observed in both the resistivity $\rho \propto T$ and specific heat $C_p/T\propto -\ln T$, characteristic of a two-dimensional antiferromagnet. The quantum critical point is accompanied by an enhancement of the spin fluctuations, as indicated by the diverging Sommerfeld coefficient $\gamma$ at $x=x_c$.

• Received 27 May 2016
• Revised 18 October 2016

DOI:https://doi.org/10.1103/PhysRevB.95.220405