We report on the depth-sensitive, temperature-dependent exchange coupling in an FePt/FeRh thin film exchange spring structure. The depth-dependent in-plane magnetisation is measured as a function of applied magnetic field and sample temperature using polarised neutron reflectometry (PNR). The magnetisation profiles are interpreted in terms of the competition between anisotropy, exchange coupling, and dipolar coupling as the FeRh undergoes the magnetic phase transition from antiferromagnetic to ferromagnetic ordering. The PNR data are combined with bulk magnetometry and X-ray characterisation, allowing us to determine characteristic length scales over which the exchange spring mechanism is effective at ambient and elevated temperatures.
|Journal||Physical Review Materials|
|Publication status||Accepted/In press - 24 Jan 2022|