Effects of Interface Roughness on Interlayer Coupling in Fe/Cr/Fe Structure

Effect of interface roughness on antiferromagnetic coupling between Fe layers in a Fe/Cr/Fe trilayer, with Cr layer having a wedge form has been studied. All the samples have been deposited simultaneously on substrates having different roughness, thus it is being considered that there is no variation in the morphological features like grain size and grain texture of the films. Measurements have been done as a function of Cr spacer layer thickness and the peak value of antiferromagnetic coupling strength is compared among different trilayers, thus any influence of spacer layer thickness fluctuation from sample to sample has also been avoided. The samples are characterized by X-ray reflectivity (XRR) and magneto-optic Kerr effect (MOKE). XRR results show that the roughness of the substrate is not replicated at the successive interfaces. Antiferromagnetic coupling between Fe layers decreases with the increase of roughness of Fe/Cr/Fe interfaces.