Magnetic phase transition in ferromagnet Co100−xErx (x=55,65x=55,65) with random anisotropy

We have investigated the magnetic phase transitions of amorphous Co45Er55 and Co35Er65, prepared by the liquid quenching technique. From an analysis of the approach to saturation magnetization some fundamental parameters have been extracted. Magnetic data taken in the critical region were analyzed using the modified Arrott plot and the critical isotherm. The data satisfy the magnetic equation of state characteristic of second order phase transition over the entire temperature range of the present investigation. The exponents values obtained are in very good agreement with the theoretical values calculated for 3D Heisenberg model.