Thermal enhancement of the antiferromagnetic exchange coupling between   Fe epilayers separated by a crystalline ZnSe spacer
  We have put into evidence the existence of an antiferromagnetic coupling between iron epilayers separated by a ZnSe crystalline semiconductor. The effect has been observed for ZnSe spacers thinner than 4 nm at room-temperature. The coupling constant increases linearly with temperature with a constant slope of ~5.5x 10-9 J/m2K. The mechanisms that may explain such exchange interaction are discussed in the manuscript. It results that thermally-induced effective exchange coupling mediated by spin-dependent on and off resonant tunnelling of electrons via localized mid-gap defect states in the ZnSe spacer layer appears to be the most plausible mechanism to induce the antiferromagnetic coupling. 
J. Varalda, J. Milano, A. J. A. de Oliveira, E. M. Kakuno, I. Mazzaro,   D. H. Mosca, L. B. Steren, M. Eddrief, M. Marangolo...