A THEORETICAL INVESTIGATION OF THE SPECIFIC-HEAT OF SUPERLATTICES IN A MAGNETIC-FIELD

We analyze the specific heat variations as a function of an external m agnetic field of a simple model of superlattice that includes (i) in-p lane ferromagnetic exchange, (ii) interplane ferromagnetic exchange, ( iii) dipolar interactions, (iv) magnetocrystalline anisotropy. The cal culations are carried out at the spin-wave level. The interplay betwee n the existence of a canting transition and the anisotropy of the stru cture generates nontrivial behavior for the spin-wave contribution to the low-temperature specific heat as a function of an external magneti c field when dipolar interactions and magnetocrystalline anisotropy ar e taken into account.