EXPERIMENTS ON INTERLAYER EXCHANGE COUPLING

The results of various experiments on interlayer exchange coupling wil l be reviewed. After a general discussion of the theoretical understan ding we deal first with 90 degrees-type coupling and show that two mec hanisms proposed by Slonczewski can explain our measured data. We furt hermore study the coupling of Fe films across CuxAu1-x alloys. For the composition with x = 0.5, the coupling strength strongly increases wi th annealing. We believe that this is due to an order-disorder structu ral transformation in the CuxAu1-x alloy. Finally, we present results on epitaxially grown bilayers Fe/EuS(100) and trilayers Fe/EuS/Fe(100) . In the latter at room temperature we observe a strong decrease in th e coupling strength as a function of the interlayer thickness, with a characteristic length of about 0.1 nm. At low temperatures in the bila yer we find an antiferromagnetic coupling between Fe and the adjacent ferromagnetic EuS.