  The magnetic order resulting from an indirect exchange between magnetic
moments provided by spin-polarized hole gas in the metallic phase of a GaMnAs
double layer structure is studied via Monte Carlo simulation. The coupling
mechanism involves a perturbative calculation in second order of the
interaction between the magnetic moments and carriers (holes). We take into
account a possible polarization of the hole gas due to the existence of an
average magnetization in the magnetic layers, establishing, in this way, a
self-consistency between the magnetic order and the electronic structure. That
interaction leads to an internal ferromagnetic order inside each layer, and a
parallel arrangement between their magnetizations, even in the case of thin
layers. This fact is analyzed in terms of the inter- and intra-layer
interactions.
