Neutron reflectivity investigations of EuS/PbS superlattices grown on (111) BaF2 substrate

The existence of the pronounced ferromagnetic interlayer correlations in EuS/PbS superlattices grown in the [111] direction on BaF2 substrate has been revealed by unpolarized neutron reflectivity measurements. This is in a stark contrast with the previous findings of antiferromagnetic interlayer coupling in a similar EuS/PbS superlattices grown in the [001] direction on KCl substrate. In order to confirm that the observed FM correlations result from interlayer exchange coupling, rather than from spurious layer magnetization alignment, the in-plane magnetic domain orientation distribution has been investigated with neutron polarization analysis.