Oscillatory interlayer exchange coupling in epitaxial Co2MnSi/Cr/Co2MnSi trilayers.

Interlayer exchange coupling (IEC) in trilayers, which consist of a full Heusler Co₂MnSi (CMS) phase as ferromagnetic layers separated by a Cr spacer layer, has been investigated. The shape of magnetization loops shows unusual oscillatory behavior with the thickness of Cr. The oscillation period is about 3.3–3.5 nm. The charecteristics of magnetization curves show that 90° coupling plays a dominant role in IEC between CMS layers. Moreover, the strength of 90° coupling turns out to be very high (up to -1.85 ergs/cm²) around the first oscillation peak. [ABSTRACT FROM AUTHOR]