Magnetic properties, electrical resistivity and thermal expansion of (Ho,Y)Co2

Abstract

The influence of the Ho substitution on the Co moments in (Ho_xY_1-x)Co₂ has been investigated by means of magnetic, resistivity and lattice parameter measurements. A first-order phase transition and a field-induced metamagnetism can be detected for x>or=0.7. At the magnetic transition temperature anomalies of the lattice parameters were measured for x>or=0.3. In connection with the first-order transition a discontinuity in the rho (T) curves appears for x>or=0.7. For 0.32 the existence of a critical RE concentration (x>0.1) for the appearance of a long-range magnetic order is evidenced. The Co moments mu _Co are compared with neutron diffraction results. The overall agreement is very good and supports the assumption of induced Co moments. For the whole pseudobinary system, a Fermi energy situated in a steep flank of the density of states function was assumed.