Spinwellen und Ummagnetisierung in antiferromagnetisch gekoppelten Schichtsystemen

Abstract

In this thesis the influence of antiferromagnetic interlayer coupling on the static and dynamic properties of ferromagnetic thin films was investigated. The negative exchange interaction is observed between Fe-layers across Crinterlayers of a few monolayers thickness. Growth of the monocrystalline Fe-layers and Cr-interlayers was monitored by AES (Auger-electron spectroscopy) and SPALEED. The Strength of the antiferromagnetic interlayer coupling was measured via the spinwave modes of the layered structures. It was found that the maximum of negative coupling strength occurs at four monolayers Cr. For increasing Cr-thickness the coupling strength then decreases and vanishes for more than ten monolayers of Cr. For the characterization of the magnetization reversal processes we used the magnetooptical Kerr-effect and the magnetoresistance effect. These reversal processes could be described theoretically by a calculation of the total magnetic anisotropy energy. It was also found that the negative coupling strength increases by lowering the temperature