monolayers of the type II antiferromagnet EuTe

A degenerate ground state spin pattern is found for the type II antiferromagnet EuTe in the bulk limit. The model system is EuTe with ferromagnetic nearest neighbor View the MathML source and antiferromagnetic next nearest neighbor View the MathML source exchange interaction. For the non-trivial ground state the spins within a single (1 1 1) plane are no longer all parallel. Instead a quarter of the spins are parallel to the NN spins in the adjacent layer. This state becomes metastable if dipolar interaction is taken into account, or for low-dimensional structures of few (1 1 1)-monolayer systems of EuTe.