Tuning of magnetization dynamics by ultrathin antiferromagnetic layers

The controlled adjustment of static and dynamic magnetic properties of ferromagnetic thin film by the use of ultrathin antiferromagnetic layers is demonstrated. Induced uniaxial anisotropy and thus precessional frequency is increased over more than one order of magnitude. Concurrently, the effective damping parameter is varied by which a significant decrease in magnetic settling time is achieved. Simple relations based on the interfacial antiferromagnetic layer contribution are derived. The use of ultrathin antiferromagnetic layers, below the thickness range for the onset of exchange bias, allows for tuning of magnetic properties beyond the established manipulation of the intrinsic ferromagnetic layer properties. (C) 2008 American Institute of Physics.