Itinerant metamagnetism in rare earth-transition metal compounds

Abstract

Intermetallic compounds of rare‐earth and transition metals present the possibility of using the large magnetic moment of the first with the high Curie temperature of the second. We first discuss the nature of the coupling between the spin of the rare‐earth and transition metal. We assume that it happens within the d band coming from the 5d and 3d levels and describe it using the Van Vleck model for ferromagnetism. We then consider the particular case of Cobalt compounds where Cobalt can be magnetic or not depending of the rare‐earth metal. We describe the appearance of magnetism as a collective metamagnetism due to the position of the Fermi level in these compounds in a steep decrease of the density of states. Calculation of the density of states confirms this hypothesis.