Itinerant-electron metamagnetism of the Hf1−xTaxFe2 (x=0.125 and 0.14) compounds under high pressure.

The effect of hydrostatic pressure on the magnetic properties has been investigated for itinerant-electron metamagnetic Hf 1− x Ta x Fe 2 ( x =0.125 and 0.14) compounds which exhibit a temperature-induced transition from the ferromagnetic (FM) to the antiferromagnetic (AFM) state upon heating. Both the magnetic transition temperature T FM–AFM and the spontaneous magnetization M S decreases with increasing pressure. The application of an external pressure leads also to the strong increase of the AFM–FM transition field μ 0 H cr . The magnitude of the pressure coefficient, dln( T FM–AFM )/d P , is much larger than that of dln( M S )/d P . This extremely large difference between the pressure coefficients is explained by the influence of spin fluctuations on the magnetovolume effects in the compounds Hf 0.875 Ta 0.125 Fe 2 and Hf 0.86 Ta 0.14 Fe 2 . [ABSTRACT FROM AUTHOR]