Pressure dependence of the Curie temperature and the spontaneous magnetization in ferromagnetic Hf(Fe,Co)2

Pressure effects on the Curie temperature and spontaneous magnetization in ferromagnetic Hf(Fe1-xCox)2 with the cubic Laves phase structure have been investigated under high pressures up to 1.2 GPa. An anomalously strong pressure dependence of the Curie temperature is observed around x=0.725. A collapse of ferromagnetic moment under pressure is also observed at x=0.6 and 0.65. These results are discussed on the basis of the spin fluctuation model of itinerant-electron metamagnetism.