Precise magnetization measurements of a half-metallic ferromagnet ${\mathrm{Co}}_2\mathrm{TiSn}$ with the Heusler type structure have been carried out under pressure up to 1.27 GPa. At ambient pressure, the spontaneous magnetic moment $M_{\mathrm{s}}^{\exp }$ and the Curie temperature $T_{\mathrm{C}}^{\exp }$ are experimentally obtained to be $1.993\left(3\right){\mu }_{\mathrm{B}}$/f.u. and $376.76\left(7\right)$ K, respectively. The $M_{\mathrm{s}}^{\exp }$ is independent of applying pressure. The $T_{\mathrm{C}}^{\exp }$ decreases with the increase of pressure and the pressure derivative of the Curie temperature $d{T}_{\mathrm{C}}^{\exp }/dp$ is estimated to be $-3.15\left(9\right)$ K/GPa. Furthermore, the pressure effect on the electronic and magnetic properties of ${\mathrm{Co}}_2\mathrm{TiSn}$ has been theoretically investigated on the basis of first-principles density functional calculations by using the projector augmented wave method in order to evaluate the half metallicity of ${\mathrm{Co}}_2\mathrm{TiSn}$. Both the experimental and the theoretical results under pressure reveal that ${\mathrm{Co}}_2\mathrm{TiSn}$ is half metal. The experimental results of pressure-dependent magnetic properties are finally discussed on the basis of the spin fluctuation theory for itinerant electron magnetism.

• Received 2 October 2017
• Revised 20 February 2018

DOI:https://doi.org/10.1103/PhysRevB.97.104414